Although either side of the filter facing the light source can play a role in filtering light, although the direction of the transmission filter has little effect on the intensity and spectrum of the emitted light, but the coating surface facing the light source will enhance the filter effect. In this way, the thermal effect or possible thermal damage caused by the radiation outside the pass band absorbed by the substrate or the colored glass filter layer can be minimized.
When using a filter, the collimated light should be incident on the surface of the filter perpendicularly (or at a designed angle). When uncollimated light or light non-perpendicularly incident on the surface of the filter, the central wavelength (the wavelength corresponding to the peak transmittance) will shift to a shorter wavelength, and the design of the transmission band (passband)-shaped lens will change. By slightly changing the incident angle, the passband of the filter can be effectively adjusted in a small range. When the incident angle changes greatly, it will cause a large change in the center wavelength, and will significantly distort the shape of the passband, and even cause a significant drop in the passband transmittance.
The influence of temperature on the filter effect of the filter
The center wavelength of the bandpass filter can be fine-tuned by changing the ambient temperature of the filter (~1 nanometer in the entire working range of the filter). This is mainly caused by slight thermal expansion or contraction of the film.
Anti-reflection filter, also known as anti-reflection filter and AR lens, is the most widely used optical filter for laser lenses in the optical coating industry.
The anti-reflection filter is a single-layer or multi-layer anti-reflection coating on the surface of optical glass or optical grade plastic. The main function of this film is to reduce or eliminate the reflected light on the surface of optical elements such as plane mirrors, prisms, and lenses, and then increase the amount of light transmitted by the optical elements to increase the luminous flux of the optical elements.
At present, the coating of anti-reflection filters (AR mirrors) is mainly coated on substrates of optical glass, optical crystal, PMMA, PC, and PET. According to different application occasions and different demand indicators, currently commonly used materials include magnesium fluoride, titanium dioxide, silicon dioxide, two high-power laser mirrors, aluminum, zirconium dioxide, ZnSe, and ZnS ceramics.膜等。 Membrane and so on.
Because the processing of the optical antireflection coating needs to be used according to the actual situation, the hardness, temperature and humidity used are considered According to the specific indicators provided by the customer, the city science and technology will make the right optical solution for the customer.
Cleaning the laser lens
1. You must wear finger cots or rubber gloves before handling the lens. Never You can touch the lens directly with your fingers.
2, only hold the edge of the lens or the mirror, and do not touch the inner film of the lens.
3. The dust on the mirror surface needs to be blown away with a blowing balloon. You cannot blow it directly against the mirror.
4. If you really need to clean the lens, you can only use a laboratory-grade paper soft cotton ball, dip in an appropriate amount of absolute ethanol or acetone, and remove the lens very lightly. The center rotates and rubs to the edge; the cotton ball needs to be replaced constantly to avoid the dirt on the cotton ball from scratching the surface of the lens
5. The lens should be placed in a dry and clean place. For detection and cleaning, a soft paper towel should be placed on the work surface before the lens can be placed on it.
6. Avoid talking to the lens; keep saliva, food, beverages and other potential contaminants away from the laser lens.
7. Handle with care, and replace the lenses that are not in use, wrap them in soft tissues and keep them properly.