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The cleaning and maintenance of laser marking filters are key steps in ensuring long-term stable operation of equipment and maintaining high-precision marking effects. Improper operation may cause damage to the film layer, decrease in transmittance, and even scrap of optical components, so it is necessary to follow the standard procedures. 1、 Preparation before cleaning Environmental requirements Operate in a dust-free or low dust environment to avoid secondary pollution. The ideal conditions are a clean workbench or anti-static operating area. Protective measures Wear dust-free finger cots or rubber gloves to prevent hand oil and sweat from coming into contact with the surface of the filter. Tool preparation Air blower (oil-free) or nitrogen tank: used to remove floating dust Anhydrous ethanol (analytical grade) or reagent grade isopropanol Fiber free wiping paper, lens paper, or long fiber cotton swab Plastic tweezers (metal tweezers are prohibited to prevent scratches) Prohibit the use of regular tissues, fabrics, or compressed air containing water/oil to prevent residual impurities from damaging the film layer. 2、 Standard cleaning steps Preliminary dust removal Use an air blower to gently blow away loose particles on the surface of the filter. Do not blow air with your mouth to prevent saliva or moisture from contaminating the surface. Gently wipe Drop a small amount of anhydrous ethanol onto the lens paper (not directly onto the filter) Hand hold the edge of the filter and slowly wipe it in a single direction (such as from the center outward) Use new cleaning paper every time you wipe to avoid repeated use that may cause dirt to deposit again Stubborn stain treatment If fingerprints or oil stains are difficult to remove, use reagent grade acetone for short-term wiping, but immediately clean the residue with isopropanol and quickly blow dry. Drying and inspection After cleaning, dry it with an air blower and visually inspect for any residual stripes or spots under white light. Correct technique: Apply gentle force, avoid back and forth friction, and prevent micro scratches from interfering with the film layer. 3、 Daily maintenance suggestions Regular inspection frequency Based on the level of dust in the work environment, it is recommended to check the status of the filter every 500 hours after operation. Installation precautions Only hold the edge of the filter to avoid touching the optical surface Ensure that the coating surface is facing the incident light direction to improve light transmission efficiency and reduce back reflection Storage protection When not in use, it should be placed in a dedicated anti-static storage box to avoid exposure to damp, high temperature, or strong light environments. System collaborative maintenance Keep the internal circulating water of the laser marking machine clean, regularly replace deionized water, and prevent scaling from affecting heat dissipation Check that the smoke exhaust system is unobstructed and reduce the risk of attachment of optical components by processing splashes 4、 Common Misconceptions and Risk Warning Using regular alcohol or household cleaning agents: may contain additives that corrode the film layer Directly touching the optical surface with fingers: even brief contact may leave irreversible fingerprints Removing the filter while turned on: There is a risk of high voltage electric shock and laser radiation, and it is necessary to disconnect the power for operation Neglecting signs of aging: If bubbles, cracks, or a significant decrease in light transmittance are found in the film layer, it should be replaced in a timely manner

The key to determining the quality of a dichroic mirror lies in its comprehensive performance of optical properties, manufacturing processes, and environmental adaptability. High quality dichroic mirrors should have precise spectral response, high reflection/transmission efficiency, excellent surface quality, and long-term stability, especially in precision optical systems where any small deviation may affect overall performance.   1、 Key Quality Assessment Indicators Spectral performance: reflectivity and transmittance   High quality dichroic mirrors should achieve high reflectivity (>95%) and high transmittance (>90%) within the target wavelength range, while having extremely low transmission or reflection in non target bands. For example, a DM505 lens used for fluorescence microscopy should have high reflectivity in the 400-450nm wavelength range and high transparency in the 500-700nm wavelength range, with a steep transition band to avoid signal crosstalk. The measured data needs to be validated using a spectrophotometer (such as PerkinElmer Lambda1050+). Wavelength Range and Cut off Characteristics   Clearly calibrate the working band (such as visible light 380-780nm or specific laser lines such as 532nm) and ensure stable performance within this range. The "cut-off" of short wave or long wave lenses should be sharp, that is, the transition interval from high reflectivity to high transparency should be as narrow as possible to improve spectral accuracy. Incident angle sensitivity (angle tolerance) Most dichroic mirrors are designed for use at a 45 ° incident angle, where high-quality products perform best and remain stable even when changing within a range of ± 5 °. Products with strong angle dependence may cause optical path deviation or efficiency reduction, affecting system alignment. Surface Quality and Defect Control The surface roughness should be ≤ 0.5nm (Ra), and the scratch/pitting grade should comply with the 20/10 standard (ISO10110-8). Medical or research grade lenses require higher surface cleanliness to avoid scattering and signal attenuation. Film adhesion and environmental stability The film layer needs to be tested using the cross cut method (ASTM D3359 Class 4B) to ensure that it does not peel off. After 500 cycles of temperature cycling (-40 ℃~+85 ℃), the performance degradation is ≤ 0.3%, reflecting its durability. Under humid and hot conditions (such as 85% RH, 85 ℃), it can still maintain stable performance and comply with the ISO9211-4 standard. Base material and damage threshold Fused silica or K9 glass substrate is preferred. The former has low thermal expansion coefficient and is suitable for high-power laser applications. High quality lenses have a damage threshold of>5J/cm ² under 1064nm laser, making them suitable for ultrafast laser systems.

The key to choosing a suitable visible light dichroic mirror is to clarify the application requirements and match the core optical parameters. The following is a systematic selection guide to help you accurately identify the appropriate model. 1、 Clarify application scenarios and determine basic types There are significant differences in the spectral response requirements of dichroic mirrors for different purposes, and priority should be given to selecting the basic type based on the usage scenario: Fluorescence microscope system Need to separate excitation light from emission fluorescence Recommendation: Long wave pass type (such as DM505), reflecting short wave excitation light (such as blue light), transmitting long wave emission light (such as green/red light) Projection and Display Devices (DLP/LCD) Used for color separation and light combination to enhance color reproduction Recommendation: Combining short wave pass and long wave pass to achieve efficient separation and recombination of RGB tricolor light Multi wavelength laser integrated output Recommendation: Bandpass or sharp cutoff type, ensuring high reflection for specific wavelengths and high transparency for others, reducing energy loss Recommendation: Wide band dichroic mirror, supporting continuous adjustable color temperature output 2、 Focus on core performance parameters After determining the type, it is necessary to focus on evaluating the following indicators to ensure the stability and efficiency of the optical system: The wavelength range determines the working spectral range (such as 400-700nm visible light), which must cover the main wavelength band of the target light source Reflectance/Transmittance Measurement of Light Energy Utilization Efficiency: Products with Reflectance>95% and Transmittance>90% are preferred It is recommended to choose a tolerance of ± 5 ° or above for the impact of incident angle changes on performance, to adapt to complex optical paths Surface quality affects imaging clarity. High precision lenses with scratches ≤ 60-40 should be selected for medical or scientific grade applications Whether it is deformed or peeled off under high power of thermal stability fused silica substrate and multi-layer compact coating products are selected Special reminder: If used in high-power laser environments (such as>1W), it is necessary to confirm that the product has good thermal management design to avoid damage to the film layer due to heat absorption. 3、 Consider physical and environmental compatibility Base material: fused silica or BK7 glass is preferred. The former is high temperature resistant, low expansion, and more suitable for precision systems Size and shape: Choose circular (e.g. 25.4mm) or square (e.g. 1 "× 1") specifications based on the optical path space Coating process: ion beam sputtering or multi-layer magnetron sputtering technology is recommended for denser and longer lifespan film layers

The key to selecting a suitable laser marking filter lies in accurately matching the laser wavelength, ensuring a high damage threshold, selecting appropriate materials and coating processes, and balancing size compatibility and system integration requirements. The following are specific selection strategies and practical suggestions: 1、 Clarify the laser type and operating wavelength The primary function of a filter is to selectively pass through the target laser wavelength, blocking stray light and harmful radiation. Therefore, precise matching must be performed based on the output wavelength of the laser used: 1064nm: Suitable for Nd: YAG or fiber lasers, widely used for marking materials such as metals and plastics 532nm (green light): used for high-precision color marking, such as electronic component identification 355nm (UV): Suitable for heat sensitive materials such as plastics and semiconductors, achieving cold processing and avoiding thermal deformation Recommend using narrowband bandpass filters that only allow target wavelengths within ± 5nm to pass through, effectively suppressing background noise and improving marking contrast and clarity. 2、 Prioritize selecting dura mater filters with high laser damage threshold Industrial grade laser marking often operates at high power, and the filter needs to have sufficient resistance to laser damage: Hard film filters (such as TiO ₂/SiO ₂ multilayer dielectric films) have higher laser damage thresholds and are suitable for long-term stable operation Although soft film filters have low cost, they are prone to thermal deformation or film erosion, and are not recommended for high-power scenarios It is recommended to choose a filter with double-sided anti reflective coating, which can increase the transmittance to over 99% and reduce energy loss

A dichroic mirror is a functional optical element designed based on the principle of optical interference, which can selectively reflect or transmit light within a specific spectral range according to wavelength. In practical applications, due to the significant differences in requirements for optical path, spatial layout, and performance parameters among different systems, it is often necessary to customize the size and specifications of dichroic mirrors. The common classification of customized sizes is mainly based on their geometric features, installation methods, and optical aperture dimensions. Circular is the most common custom shape, with diameters typically measured in millimeters. Common specifications include standard sizes such as 12.7mm (1/2 inch), 25.4mm (1 inch), 50.8mm (2 inches), and also support special requirements for non-standard diameters such as 30mm, 40mm, 60mm, etc. These circular lenses are widely used in microscopy imaging systems, laser beam combining devices, and fluorescence detection equipment, making them compatible with standard barrels and brackets. Rectangular or square dichroic mirrors are commonly used in compact optical modules or linear scanning systems. Their side length ratios are flexible and can match the incident light field according to the shape of the light spot, reducing edge obstruction and improving light energy utilization. This type of size is commonly found in industrial visual inspection and multispectral imaging equipment. In addition, there are customized shapes such as ellipses or structures with installation slots, mainly used for integrated optical systems with limited space or requiring precise positioning. From a usage perspective, size selection directly affects the degree of freedom in optical path design and the stability of the system. For example, in confocal microscopy, a dichroic mirror with a diameter of 25.4mm and a thickness of 3.2mm is usually used to ensure precise matching with the filter wheel assembly and achieve efficient separation of excitation light and emission light; In multi laser beam applications, large-sized products such as 50.8mm and above can reduce power density, avoid film damage caused by local overheating, and provide greater adjustment margin. Small size customization is common in portable testing instruments, balancing lightweight and functional integration. Overall, the size customization of dichroic mirrors requires comprehensive consideration of factors such as mechanical assembly space, beam divergence angle, adaptability to incident angle, and thermal management. Through reasonable selection, the optimal balance between optical performance and system integration can be achieved.

The models of dichroic mirrors are mainly divided based on their spectral characteristics, incident angle, substrate materials, and application scenarios. Different manufacturers will provide diversified products based on standard or customized requirements. The following are common and representative model classifications and specific examples: 1、 Typical model types classified by spectral characteristics Longpass Dichroic Mirrors Reflects short wavelength light and transmits long wavelength light, commonly used in fluorescence microscopes to separate excitation light and emission light. Example models: DM405, DM455, DM505 Flu-TS400 in the Flu TS series has high transparency in the range of 320-380nm and reflects light at 425-480nm. Shortpass Dichroic Mirrors Reflects long wavelength light and transmits short wavelength light, suitable for UV/visible light separation scenes. Example model: DM390 Reflects 200-390nm ultraviolet light at 45 ° incidence, with high transmittance of 400-1700nm visible and near-infrared light, suitable for high-power laser systems. Bandpass or Sharp Cut Dichromics Having an extremely narrow transition band, it achieves high-precision spectroscopy and is commonly used in scientific research grade optical systems. Example models: 66232, 66233 Specially designed for the 240-255nm wavelength range, it has high reflectivity and polarization insensitivity, and needs to be used in conjunction with a specific casing. Multiband Dichroic Mirrors Supports multiple transmission bands and one reflection band for complex optical path integration. Example model: 740 nm/940 nm multi band mirror Commonly used in multi-color imaging systems, such as the MB25.4mm specification product provided by LBTEK. UV/VIS and UV/IR types Optimized for UV laser applications, supporting broadband visible or infrared transmission. Standard model series: 193/V-FR45, 266/V-FR45, etc Based on fused silica substrate, it is suitable for 193nm to 353nm UV wavelength reflection, and transmits visible and near-infrared light at the same time.

This article mainly introduces common optical materials, their application fields, and the transmission range of optical materials, in order to provide technical references for the design and production of optical filters and lenses. This article mainly introduces common optical materials, their application fields, and the transmission range of optical materials, in order to provide technical references for the design and production of optical filters and lenses. H-K9L K9 glass (equivalent to BK7 glass) is the most commonly used colorless optical glass, with high hardness and good scratch resistance but a large coefficient of thermal expansion. It is not recommended for temperature sensitive applications and has been widely used in visible and near-infrared optical devices such as filters, flat mirrors, optical lenses, prisms, etc. K9 glass transmittance range: 330nm to 2100nm. Fused quartz series Due to its excellent thermal stability, fused quartz is commonly used in environments with high temperature requirements. The commonly used grades of fused quartz materials are JGS1, JGS2, JCS3. JGS1 is commonly used in the ultraviolet, visible, and near-infrared bands, and the material does not contain bubbles or impurities. JGS1 transmittance range: 170nm to 2100nm. JGS2 is commonly used for mirror substrates, and the material contains many small bubbles. JGS2 transmittance range: 260nm to 2100nm. JGS3 has good transmittance in infrared, but it contains many bubbles, which limits its widespread use. JGS3 transmittance range: 185nm to 3500nm. quartz crystal Quartz crystals are widely used in industries such as precision electronics, precision optics, and laser technology due to their excellent piezoelectric properties, low thermal expansion coefficient, and excellent mechanical and optical properties. Quartz crystals have low stress birefringence and high refractive index uniformity. The transmission range of quartz crystals is from 200nm to 2500nm. Magnesium fluoride (MgF2) Magnesium fluoride crystal is an ideal optical material mainly used for optical prisms, optical lenses, optical filters, and various other optical components. Magnesium fluoride crystals have extremely high resistance to mechanical and thermal shock and radiation. Her light transmission range is very wide, covering from deep ultraviolet at 120nm to far-infrared at 7000nm. Magnesium fluoride is widely used in high-tech fields such as optics, optical instruments, fiber optic communication, laser technology, integrated optics, cold light sources, photochromic pigments, automobiles, communication equipment, toys, handicrafts, etc. Transmittance range of magnesium fluoride: 120nm to 7000nm Calcium fluoride (CaF2) Calcium fluoride has excellent UV to mid infrared transmittance properties. Calcium fluoride (CaF2), commonly used as an optical device for quasi molecular lasers, has a refractive index of 1.428 at a wavelength of 1.064 µ m and high mechanical and environmental stability. Calcium fluoride is highly suitable for applications that require low damage threshold, low fluorescence, and high uniformity, and is widely used in infrared windows, prisms, and optical lenses. Calcium fluoride transmittance range: 170nm to 7800nm Zinc Selenide (ZnSe) Zinc selenide is a very good infrared material with a wide transmission range. Due to its excellent imaging and thermal shock properties, it is often used as a lens for carbon dioxide lasers and optical filter windows. Zinc selenide is widely used in fields such as lasers, medicine, astronomy, and infrared night vision. Transmittance range of zinc selenide: 500nm to 19000nm Gemstone (Al2O3) Gemstone (also known as sapphire) is a type of corundum, which is a material with extremely high hardness. It has superior mechanical performance and a very wide range of light transmission, and is often used in fields that require high surface scratches on optical components. It is widely used in infrared military devices, satellite space technology, high-intensity laser window materials for civil aerospace, military industry, etc., such as transparent windows, fairings, optoelectronic windows, protective plates, gyroscopes, wear-resistant bearings and other components. Military optoelectronic equipment, such as electro-optical pods, electro-optical trackers, infrared surveillance systems, submarine electro-optical masts, etc. Gemstone (Al2O3) transmittance range: 180nm to 4500nm Silicon (Si) Silicon is a commonly used optical material in the mid infrared band, which is widely used in military equipment, security monitoring, and other fields. Its transmission band has a good transmittance of 3 to 5 microns and is widely used in industries such as aerospace, electronics and electrical, construction, transportation, energy, chemical, textile, food, light industry, medical, and agriculture. Transmittance range of silicon (Si): 1200nm to 7000nm Germanium (Ge) Germanium is a commonly used far-infrared optical material with a very high optical refractive index. It is commonly used in infrared imaging, infrared temperature detection, and especially in the early 2020 pandemic, which greatly stimulated the development of infrared imaging and infrared temperature detection equipment. The application of germanium (Ge) optical filters has also been more widely popularized. Germanium (Ge) transmittance range: 2000nm to 1400nm  

Vascular vascular filter is an optical filter specifically used for the treatment of blood vessels or sensitive skin in ultra photon rejuvenation machines.   Vascular filters, as the name suggests, are designed for vascular problems. The main operating range of vascular filters is between 530nm-650nm and 900nm-1200nm. So what is the function of vascular filters? Short wavelength optics can target and treat superficial vascular lesions with optimal absorption rates of oxygen, hemoglobin, and reduced hemoglobin between 530nm-650nm. At the same time, the competitive absorption of melanin is weaker in the shallow wavelength range, resulting in a more concentrated effect on blood vessels. Long wavelength penetration is deeper, which can target deep vascular lesions. The penetration is deeper in the 900nm-1200nm wavelength range, and the absorption rate of oxygenated hemoglobin begins to increase again at 900nm, resulting in more concentrated light absorption, improved capillary dilation, and reduced adverse reactions. Therefore, based on these two characteristics, vascular filters can significantly improve capillary dilation. Combining the two bands for treatment results in higher absorption rates and deeper penetration depths, leading to better outcomes. (Reminder: All skin rejuvenation equipment should be used under the guidance of professionals.)

Polarizing film is an optical component that can separate the vibration direction in natural light into two directions. Polarizers have applications in many fields, including displays, photography, optical instruments, etc. In the optical path, polarizers can play the following roles: Controlling the direction of light: Polarizers can change the polarization direction of light, thereby controlling the direction of light. For example, in liquid crystal displays, polarizers can polarize the light emitted by the backlight and then change its polarization direction to achieve image display. Control the intensity of light: Polarizers can absorb light in specific directions, thereby controlling the intensity of light. For example, in a solar mirror, polarizing film can absorb scattered light, thereby improving the clarity of the field of view. Control the color of light: Polarizers can change the color of light. For example, in a colored polarizer, the polarizer can absorb light of a specific wavelength, resulting in the light appearing in a specific color. Classification of Polarizers According to the function of polarizing film, polarizing film can be divided into four types: transmissive, reflective, semi transmissive and semi reflective, and compensating. Transmitting polarizer: After passing through the polarizer, the light maintains its original direction. Reflective polarizer: Light is reflected after passing through the polarizer. Semi transparent and semi reflective polarizing film: After passing through the polarizing film, light partially passes through and partially reflects. Compensating polarizer: used to eliminate color distortion in LCD displays. According to the dyeing method, polarizers can be divided into two types: iodine based and dye based. Iodine polarizing film: It has optical properties of high transmittance and high polarization degree, but poor resistance to high temperature and high humidity. Dye based polarizing film: It has good high temperature and humidity resistance, but its transmittance and polarization degree are not as good as iodine based polarizing film. Application of polarizing film: Polarizers have a wide range of applications in optical paths, such as: LCD display: The polarizer in LCD display is a key component for achieving image display. Sunglasses: Polarizers in sunglasses can improve field of view clarity and reduce glare. 3D glasses: The polarizing film in 3D glasses can achieve stereoscopic display. Optical instruments: Polarizers in optical instruments can be used for optical measurement, optical design, etc.  

What are commonly referred to as optical insulation sheets, thermal mirrors, and infrared reflectors in the field of optics? Thermal mirrors, also known as thermal reflection mirrors, optical insulation sheets, and infrared reflection sheets, are just names used by customers in different application fields. Apart from some differences in specific dimensions and optical parameters, they are commonly referred to as optical thermal mirrors in the field of optics. A thermal mirror is a type of thermal reflector designed to serve as a short pass band filter, capable of transmitting visible light wavelengths at a 0 ° incident angle while reflecting near-infrared light and heat generating wavelengths. Remove unwanted heat from the optical system. Specific dimensions and parameters can be customized according to customer specific requirements. The lenses produced by our company have high near-infrared energy isolation (cut-off from 720nm~2500nm); Effectively isolate sunlight and heat from metal halide lamps, ensuring 90% effective utilization of visible light reflection and 10% absorption for complete insulation; High temperature resistant glass, no breakage! There are two options to choose from: UV cutoff and non cutoff, with long-term stock available in both large and small batches. Thermal Mirror Product Specifications Type: Hot Mirror Incident angle 0 °± 10 ° or 45 ° Transmission range 420-700 nm (other parameters can be customized) Transmittance ≥ 85% (other parameters can be customized) Reflection band 725-2500 nm (other parameters can be customized) Reflectance Ravg ≥ 90% 725-2550 nm (other parameters can be customized) Thickness tolerance ± 0.1 mm Dimensional tolerance ± 0.1 mm Optical aperture ≥ 90% Maximum safe temperature: Green board: 150 ℃ Tempered glass: 250 ℃ Heat resistant glass: 450 ℃ Danyang Qiaosi Import and Export Co., Ltd. specializes in the production of various optical insulation films, infrared cut-off filters, mobile phone camera filters, camera filters, insulation films, digital camera filters, security camera filters, CCD filters, crystal films, night vision filters, color filters, lens filters, filters, spectrometers, reflectors, prisms, lenses, infrared transparent acrylic sheets, panels and window panels, and other optical products. Our company specializes in providing fiber optic lighting, LED lighting, gold halide lamp insulation, light engines, and high-precision digital cameras with filters to eliminate CCD near-infrared interference, ensuring the normal operation of optoelectronic instruments and equipment  

Attention should be paid to the following issues during the processing of polarizing films: Temperature control: During the process of polarizing film processing, it is necessary to control the temperature of the processing environment to avoid plastic deformation or loss of control of the polarizing film due to excessively high or low temperatures. Pressure control: During the processing, it is necessary to control the processing pressure. Excessive pressure can cause deformation of the polarizer, while insufficient pressure can lead to product instability or poor quality. Cutting technology: Polarizers require special cutting techniques to maintain product stability and accuracy. Quality inspection: The processed polarizing film needs to undergo strict quality inspection, including appearance inspection, optical performance testing, etc., to ensure that the product meets the specified quality standards. Storage conditions: Polarizers need to be protected from strong mechanical vibrations, moisture, high temperatures, and other factors during processing and storage to avoid affecting the stability and quality of the product.

Filter is an important optical device in optical systems, which achieves light regulation by selectively transmitting or blocking light of specific wavelengths. Filters play an important role in many fields, including optics, optoelectronics, image processing, photography, and spectroscopic analysis. So what are the functions and importance of the filter we are talking about? Control and adjustment of light by filter: Filters can selectively transmit or block light of specific wavelengths, allowing only light of specific colors or wavelengths to pass through. Filters allow us to control the characteristics of light, such as color, brightness, and contrast, to meet the needs of different applications. Filter in image enhancement and improvement: Filters are widely used in image processing and photography. By selectively filtering out or enhancing specific wavelengths of light, they can improve the quality, color brightness, and contrast of images. For example, polarizing filters can reduce light reflection and scattering, providing clear images. Filter in Spectral Analysis and Research: Filters play an important role in spectral analysis. Different types of filters can selectively transmit or block light of specific wavelengths, allowing us to separate and study spectral characteristics within a specific wavelength range. Filters are crucial for material analysis, spectral measurement, and scientific research. Filter optimization in optical system: Filters can be used to optimize the performance and functionality of optical systems. By selecting appropriate filters, we can reduce light interference and noise, and improve the signal-to-noise ratio of the optical system. Filters can also serve as isolation and protection in optical devices, enhancing the stability and reliability of the system. Filter has a wide range of applications: Filters can be found in optical instruments, camera lenses, microscopes, lasers, solar cells, and other devices. Filters are also widely used in fields such as lighting design, optical communication, fluorescence microscopy, and medical diagnosis.

Optical filter is an important optical component with the characteristic of selectively transmitting or reflecting light. Optical filters have a wide range of applications in the industrial field, including protection, precise measurement, spectral analysis, image processing, etc. The application of optical filters in industry can be divided into the following aspects: protective effect Optical filters can be used to protect optical components from harmful light damage. For example, in laser processing, using optical filters can prevent laser damage to optical components precise measurement Optical filters can be used to improve the accuracy of optical measurements. For example, in spectral analysis, using optical filters can improve the sensitivity and resolution of the spectrometer. spectral analysis Optical filters can be used to analyze the composition of substances. For example, in chemical analysis, optical filters can be used to analyze the chemical composition of substances. Image processing: Optical filters can be used to process images. For example, in photography, using optical filters can adjust the color, contrast, and brightness of the image. Specific application cases of filter: In laser processing, the use of optical filters can prevent laser damage to optical components. For example, when cutting metal, using optical filters can prevent laser damage to the lens. In spectral analysis, the use of optical filters can improve the sensitivity and resolution of spectrometers. For example, when analyzing minerals, using optical filters can improve the ability to identify mineral composition. In chemical analysis, optical filters can be used to analyze the chemical composition of substances. For example, when analyzing water quality, optical filters can be used to analyze pollutants in the water. In photography, using optical filters can adjust the color, contrast, and brightness of the image. For example, using a dimming filter can reduce the intensity of light, resulting in clearer photos.  

In the field of optics, filter is an extremely important optical component that plays a crucial role in numerous technological applications. What is the function of a filter? A filter, in simple terms, is an optical device that selectively transmits light of a specific wavelength or band while blocking light of other wavelengths or bands. The working principle of a filter is based on the characteristics of light interference, diffraction, and absorption. There are many classifications of filters. According to spectral characteristics, it can be divided into bandpass filters, cutoff filters, long wave pass filters, and short wave pass filters. A bandpass filter only allows light within a specific wavelength range to pass through, like the narrowband filter commonly used in fluorescence microscopes, which can accurately select the wavelength range for excitation and emission of fluorescence. Cut off filters start cutting off at specific wavelengths or allow light shorter than that wavelength to pass through, known as short wave cut filters; Or allow light longer than this wavelength to pass through, that is, long wave cut filters. According to the production process and materials of filters, they can be divided into thin film filters, glass filters, and crystal filters. Thin film filters achieve filtering function by depositing multiple layers of optical thin films on the substrate, and have advantages such as small size and stable performance. Glass filters usually add specific absorbents to glass to achieve filtering, commonly including colored glass filters. Crystal filters utilize the birefringence or electro-optic effect of crystals to achieve filtering, such as lithium niobate crystal filters used in some high-precision optical instruments. In astronomical observations, filters can help astronomers filter out specific wavelengths of light, allowing for better observation of distant galaxies, stars, and planets. By using specific filters, it is possible to observe invisible light bands such as ultraviolet and infrared, and obtain more information about celestial bodies. In the medical field, filters have important applications. In laser therapy, the filter ensures that only specific wavelengths of laser reach the treatment site, improving the accuracy and safety of the treatment. In ophthalmic surgery, doctors use specific filters to ensure that the laser only acts on the eye tissue in need of treatment, without causing damage to surrounding healthy tissues. Filter plays an important role in industrial production. In a color sorter, filters help distinguish materials of different colors and qualities. Accurately screen high-quality products based on the wavelength difference of reflected or transmitted light from materials, improving production efficiency and product quality. In laser radar applications, filters effectively filter out stray light in the environment, ensuring that the receiving end only receives reflected light from specific laser sources, improving the accuracy and precision of distance measurement, and providing reliable data support for fields such as autonomous driving and geographic surveying. The field of scientific research cannot do without filters. In physics experiments, researchers use filters to obtain light of specific wavelengths and study the interaction between light and matter. In chemical analysis, a specific wavelength of light is selected through a filter to excite the sample and achieve analysis of its composition and structure. In fluorescence microscopy, multiple filters are typically used to observe the sample. The excitation filter selects light of a specific wavelength that excites the sample to produce fluorescence, while the emission filter filters out the excitation light and other stray light, allowing only the fluorescence of a specific wavelength emitted by the sample to pass through and clearly observe the structure and characteristics of the sample. In the research and production of solar cells, filters are used to simulate different wavelengths of sunlight, evaluate the performance of solar cells under different lighting conditions, and provide important basis for improving the efficiency of solar cells. As an important optical component, filters play a crucial role in many fields such as astronomy, medicine, industry, and scientific research.

The principle, structure, and application of polarizing film in the field of machine vision recognition 1、 Introduction: In the field of optics, polarizing film is an important optical component. It can selectively transmit light in a specific polarization direction and control and adjust the polarization state of the light. Polarizers have a wide range of applications, from everyday sunglasses and LCD displays to machine vision recognition in the industrial field, all of which rely on their presence. This article will delve into the basic principles and structures of polarizing films, as well as their principle analysis in the field of machine vision recognition 2、 The basic principle of polarizing film: Light is an electromagnetic wave, and the vibration direction of its electric and magnetic fields is perpendicular to the direction of light propagation. In its natural state, the direction of light vibration is random, and this type of light is called natural light. Polarized light refers to the vibration direction of light within a specific plane, which has a specific directionality. The basic principle of polarizing film is based on the polarization characteristics of light and the dichroism of matter. Dichromaticity refers to the ability of certain substances to absorb or transmit light that vibrates in different directions. The materials in polarizing films, such as iodine molecules or polyvinyl alcohol, have this birefringence and can selectively absorb or block polarized light perpendicular to a specific direction, allowing only light in a specific polarization direction to pass through. Specifically, when natural light is incident on a polarizer, only polarized light with the same polarization axis direction as the polarizer can pass through smoothly, while polarized light in other directions is absorbed or reflected. In this way, polarizers achieve control and screening of the polarization state of light. 3、 Structure of polarizing film Polarizers are usually composed of multiple layers, mainly including the following parts: 1. Polarization material layer This is the core part of the polarizer, composed of materials with birefringence. Common polarizing materials such as polyvinyl alcohol (PVA) have a certain directionality in their molecular arrangement after stretching and iodination treatment, thereby achieving polarization function. 2. Protective film Located on both sides of the polarizing material layer, it serves to protect the polarizing material from external environmental influences. Protective films usually have good wear resistance, chemical corrosion resistance, and high temperature resistance. 3. Pressure sensitive adhesive layer Used to attach polarizing film to other optical components or equipment, ensuring the stability and firmness of the polarizing film. 4. Release film When the polarizer is not in use, it covers the pressure-sensitive adhesive layer to protect it. When using polarizing film, peel off the release film. In addition, in order to improve the performance of polarizers, other coatings or structures may be added, such as anti reflective coatings, anti reflective films, etc. 4、 Principle analysis of polarizing film in the field of machine vision recognition Machine vision recognition is the use of computers and image acquisition devices to obtain images, and to analyze and process the information in the images through algorithms, in order to achieve tasks such as recognition, detection, and measurement of target objects. Polarizers play an important role in this process. 1. Reduce reflection and glare In many machine vision application scenarios, such as metal surface detection, glass product detection, etc., the reflection and glare on the surface of objects can seriously interfere with the quality of images, leading to misjudgment or inaccurate detection. Polarizers can effectively reduce reflection and glare because reflected light usually has a specific polarization direction, which can be filtered out by using polarizers, thereby improving the contrast and clarity of images. For example, when detecting scratches or defects on metal surfaces, reflected light can make the scratches less noticeable. By installing polarizing film in front of the image acquisition device and adjusting its polarization direction, the reflected light can be significantly reduced, making scratches clear and visible, and improving the accuracy of detection. 2. Enhance the contrast of the image For some objects or scenes with low contrast, polarizers can enhance the contrast of the image by selectively transmitting light in specific polarization directions. This helps highlight the features of the target object, making it easier for machine vision systems to recognize and analyze. For example, when detecting small components on a printed circuit board, the image contrast is low due to the small color and brightness differences between the components. The use of polarizing film can enhance the contrast between components and the background, making it easier for machine vision systems to accurately identify and locate components. 3. Eliminate background interference In some cases, background light may interfere with the detection of target objects. Polarizers can filter out interference components in the background light by adjusting the polarization direction, making the target object more prominent. For example, when detecting impurities inside a transparent object, background light can interfere by passing through the transparent object. The use of polarizing film can reduce the influence of background light and make impurities easier to detect. 4. Polarization encoding In some complex machine vision systems, polarizers can also be used for polarization encoding. By combining multiple polarizers with different polarization directions, unique polarization encoding information can be assigned to different regions or objects in the image. Then, by processing and decoding the encoded image, more information about the shape, texture, and depth of the object can be obtained. For example, in a 3D machine vision system, images of objects in different polarization states can be obtained through polarizers with different polarization directions and multiple image acquisition devices, thereby achieving accurate measurement and reconstruction of the three-dimensional shape of the object. 5. Used in conjunction with other optical components Polarizers are often used in conjunction with other optical components such as lenses, filters, etc. to achieve more complex optical functions. For example, combining with a lens can adjust the focus and imaging effect of light, while combining with a filter can select specific wavelengths of light for detection. In practical machine vision recognition systems, it is necessary to select the appropriate polarizer type, polarization direction, and installation method based on specific application scenarios and detection requirements to achieve the best detection effect. At the same time, it is necessary to combine advanced image processing algorithms and machine learning techniques to accurately analyze and recognize polarized images. 5、 Conclusion Polarizers, as an important optical component, are based on the polarization characteristics of light and the dichroism of matter. Through carefully designed structures, they achieve control over the polarization state of light. In the field of machine vision recognition, polarizers play a key role in improving image quality and detection accuracy by reducing reflection and glare, enhancing contrast, and eliminating background interference. With the continuous development of machine vision technology and the increasing demand for applications, higher requirements will be put forward for the performance and application of polarizers, further promoting the innovation and development of polarizer technology. In the future, we can expect polarizers to play a more important role in machine vision recognition and the wider field of optics, bringing more convenience and innovation to human production and life.  

The most important perception organ in the driving scheme of autonomous vehicles is LIDAR (Light Detection and Ranging Radar). The widespread adoption of LIDAR LiDAR has brought autonomous vehicles closer to us ordinary people. What are the optical bands used for LIDAR LiDAR? What are the advantages and disadvantages of different optical bands of LIDAR lidar? The full name of LIDAR is Light Detection and Ranging Laser Detection and Ranging, also known as Optical Radar. The working principle of LIDAR: Infrared band (currently commonly used are 850nm filter band, 905nm filter band, and 1550nm filter band for emitting, reflecting, and receiving to detect objects). The 1550nm indium gallium arsenide (InGaAs) currently used in unmanned vehicles is safer compared to 905nm silicon photodetectors, as it can increase the power of the laser without harming eye health. At present, the infrared laser in the 905nm filter band cannot have too high a power due to legal regulations, because 905nm red light is invisible but can be directly transmitted to the human retina. Therefore, the detection distance of 905nm infrared light cannot meet the detection requirements of autonomous vehicles. So LiDAR radar needs to achieve a detection distance of 200-300 meters, and infrared light in the 1550nm band can meet the requirements (light greater than 1400nm cannot be projected onto the retina). Currently, infrared light in the 1550nm band is also a relatively mature application detection solution abroad. A well-known enterprise in the field of solid-state LiDAR uses 1550nm LiDAR laser with a power 40 times that of traditional silicon optoelectronic systems. After comparison, it is found that it can not only improve the signal-to-noise ratio and reduce the pulse width, but also has a low pulse repetition frequency and duty cycle. At the same time, it can improve the effective detection range of the laser radar, especially in complex weather conditions where the reflectivity of the detected object decreases, resulting in a shorter effective range of the laser radar. However, increasing the 1550nm laser radar power can further solve this problem. Even for objects with relatively low reflectivity, the effective range of laser radar from well-known companies in the industry can reach 200 meters.  

In recent years, there have been many directions of use in the field of fiber laser equipment, such as laser marking that is commonly used in many fields, laser cutting that is used in the machining field, and an increasing number of automated production lines using laser welding equipment. The popularization of laser welding equipment in automated production lines has further improved production efficiency and product yield. So what role does the laser filter in the laser welding head, which is an important component, play? The role of protecting window lenses in laser welding: Laser welding equipment generates a large amount of smoke and other pollutants during the processing and welding process. Therefore, a high-quality laser protective window lens with anti pollution performance can protect the internal components of the equipment and work stably for a long time, reducing the maintenance cost of the laser equipment in the later stage. The role of the vibrating mirror in laser welding: In laser welding, the vibrating mirror projects the laser beam onto two mirrors (scanning mirrors), and the reflection angle of the mirrors is controlled by a computer. These two mirrors can scan along the X and Y axes respectively, thereby achieving the deflection of the laser beam. The laser focal point with a certain power density moves on the marking material as required, leaving permanent marks on the material surface. The focused spot can be circular or rectangular.  

In optical system design, the performance of narrowband filters directly determines the accuracy of signal acquisition. As the "core component of spectral screening", the center wavelength and bandwidth are the core parameters that determine the "spectral positioning ability" of the filter among the six key indicators (center wavelength, bandwidth, peak transmittance, cutoff depth, damage threshold, temperature stability). This article combines practical application scenarios to analyze the technical connotations and selection points of these two indicators, helping you avoid procurement misunderstandings. 1、 Center wavelength (CWL): GPS coordinates for spectral localization 1. Definition and core role of indicators The transmission spectrum of narrowband filters shows a bell shaped curve, and the wavelength corresponding to the highest point of the curve is the center wavelength, which is the core parameter of the filter's "aiming target spectrum". For example, the filter used for 1064nm laser protection must have its center wavelength strictly aligned with the laser wavelength, and a deviation exceeding ± 3nm may result in protection failure. 2. Key impacts in application scenarios Fluorescence imaging: It is necessary to match the emission peak of the fluorescent probe (for example, FITC probe requires a 525nm center wavelength filter, deviation>5nm will cause signal attenuation); Lidar: If the center wavelength of the 1550nm band filter drifts to 1560nm, the ranging accuracy will decrease due to atmospheric window shift; Medical testing: Blood component analysis equipment relies on a 540nm center wavelength filter to capture the characteristic absorption of hemoglobin, and wavelength deviation directly affects the calculation error of biochemical indicators. 3. Selection and Avoidance Guide Pay attention to distinguishing between "design wavelength" and "measured wavelength". High quality manufacturers will provide temperature drift curves ranging from -40 ℃ to 85 ℃ (typical value ≤ 0.1nm/℃). For high-temperature environments (such as industrial furnace detection), products with temperature compensation film systems should be selected. 2、 Bandwidth (FWHM): The 'Wide Width Control Valve' for Spectral Channels 1. Technical meaning of full width at half maximum (FWHM) Bandwidth refers to the wavelength range in which the transmittance of a filter reaches its peak of 50%, reflecting the "spectral purity" of the filter. For example, labeling 532nm@5nm The filter only allows light with a wavelength of 529.5-534.5nm to pass through (transmittance ≥ 50%). 2. Balancing the application of wide and narrow bandwidth Narrow bandwidth (<10nm) ✔  Advantages: High spectral resolution, suitable for trace substance detection (such as heavy metal analysis in water quality) ✖  Disadvantage: Low light flux, requiring the use of high-sensitivity detectors Wide bandwidth (>50nm) ✔  Advantages: High signal strength, suitable for low light scenarios (such as night vision devices) ✖  Disadvantage: Easy to introduce stray light, resulting in a decrease in signal-to-noise ratio 3. Typical industry application references Semiconductor detection: The identification of silicon wafer defects requires a 1100nm filter with a bandwidth of 2nm to accurately avoid interference from the intrinsic absorption edge of silicon materials; Environmental monitoring: Atmospheric ozone detection uses a 305nm filter with a 10nm bandwidth to balance UV signal intensity and suppress solar spectral noise; Consumer electronics: NIR filters for multi camera systems on mobile phones typically use a 50nm bandwidth to ensure the transmission of infrared signals while reducing costs. 3、 Filter Knowledge Extension: Common Q&A Q1: The narrower the bandwidth, the clearer the imaging? ✓ Not necessarily! Narrow bandwidth will reduce the amount of light passing through, and for nighttime scenes, a balance between bandwidth and sensitivity is required. It is recommended to choose products with a bandwidth of 20-30nm. Conclusion: Selecting the right indicators for the filter makes spectral screening more accurate The central wavelength determines the "capture position" and the bandwidth determines the "capture purity", which together constitute the "spectral screening core capability" of narrowband filters.

In the field of optical technology, filter is an indispensable core component widely used in fields such as photography, medical equipment, laser technology, astronomical observation, and industrial testing. The performance of the filter directly determines the effectiveness of the optical system, and the number of coating layers on the filter is one of the key factors affecting its performance. As a professional coating manufacturer specializing in the production and manufacturing of optical filters, we are always committed to providing customers with high-performance and high reliability filter solutions. This article will delve into how the number of coating layers on a filter affects its performance and provide you with professional analysis. The basic principle of filter coating Filter coating is a process that achieves specific optical functions by depositing multiple layers of thin films on the surface of optical substrates. The thickness and material of each layer of film will affect the transmittance, reflectivity, and wavelength selectivity of the filter. The core goal of filter coating is to achieve selective transmission or blocking of specific wavelengths of light, thereby meeting the needs of different application scenarios. The influence of coating layers on the performance of optical filters 1. Transmittance and Reflectivity The increase in the number of coating layers on a filter usually significantly improves its transmittance and reflectance performance. Multilayer coating can enhance the transmittance of specific wavelengths through interference effects while suppressing reflections of other wavelengths. In narrowband filters, increasing the number of coating layers can more accurately control the bandwidth and peak wavelength of the transmission spectrum. Our factory ensures the optimal balance between high transmittance and low reflectance of the filter by optimizing the coating layer and material combination. 2. Wavelength selectivity The more layers of coating on a filter, the stronger its ability to control wavelength selectivity. Multi layer coating can achieve precise filtering of specific wavelengths by designing different optical thicknesses and refractive indices. In infrared filters, increasing the number of coating layers can more effectively block visible light and improve the transmittance of infrared light. This characteristic is particularly important in laser technology and medical equipment. 3. Durability and stability The increase in the number of coating layers can also affect the durability and stability of the filter. Multilayer coating can enhance the scratch resistance, corrosion resistance and aging resistance of the filter, thus extending its service life. Our company adopts advanced coating technology and high-quality materials to ensure that the filter can maintain excellent performance in various harsh environments. 4. Cost and process complexity Although increasing the number of coating layers can improve the performance of the filter, it will also increase production costs and process complexity. Each layer of coating requires precise control of thickness and uniformity, which places higher demands on production equipment and technology.

Optical filters are ubiquitous in our daily lives, from precision and optical equipment, display devices to optical thin film applications in everyday life; For example, the glasses, digital cameras, various household appliances, infrared sensing devices, and applications in autonomous vehicles that we usually wear are all manifestations of the application of optical thin film technology products. Filter products are mainly classified according to spectral bands, spectral characteristics, film materials, and application features. The principle of filter: A filter is made of plastic or glass with special dyes added. A red filter can only allow red light to pass through, and so on. The transmittance of glass sheets was originally similar to that of air, allowing all colored light to pass through, making them transparent. However, after dyeing, the molecular structure changes and the refractive index also changes, resulting in changes in the passage of certain colored light. For example, a beam of white light passing through a blue filter emits a beam of blue light, while green and red light are very rare and mostly absorbed by the filter. Characteristics of filter: Its main feature is that the size can be made quite large. Thin film filter, with a longer wavelength of transmission, is commonly used as an infrared filter. The latter is a low order, multi-stage series solid Fabry Perot interferometer formed by alternately forming metal dielectric metal films or all dielectric films with a certain thickness on a certain substrate using vacuum coating method. The selection of material, thickness, and series connection method for the membrane layer is determined by the required center wavelength and transmission bandwidth λ. Spectral band of filter: UV filter: Its main feature is to allow light with a certain bandwidth near a certain wavelength (wavelength less than 400nm) to pass through, while cutting off light in other ranges. The visible filter and visible light range from 400nm to 700nm, which can be cut off in the visible light band or highly transmitted in the visible light band. It can be customized and produced according to specific needs. Infrared filter: Its main feature is the absorption of infrared rays by the infrared band absorption plate, and the penetration of visible light. It is widely used in monitoring systems, infrared devices, automatic optical detection equipment, imaging equipment, monitoring systems, counterfeit inspection equipment, infrared cameras, and other fields. Spectral characteristics of filters: bandpass filter, cutoff filter, spectral filter, neutral density filter, reflective filter; Film layer materials for filter: soft film filter, hard film filter; Hard film filter not only refers to the hardness of the thin film, but more importantly, its laser damage threshold, so it is widely used in laser systems, while soft film filter is mainly used in biochemical analyzers. Filters are divided into color filters (flat glass or gelatin sheets of various colors, with a transmission bandwidth of several hundred angstroms, often used in broadband photometry or installed in stellar spectrometers to isolate overlapping spectral levels) and thin film filters (with longer transmission wavelengths, often used as infrared filters)