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Industrial Filters | ||
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UV & IR Cut Download Sales Sheet | ||
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UV-cut filters are long pass filters that block the UV wavelength range and transmit the visible. These filters use an absorptive glass, which is robust, cost-effective and insensitive to angle of incidence. In machine vision applications they are used in front of a lens on a CCD or CMOS camera to protect the sensor from UV light, in absence of internal protection in the camera. In addition, they are often used to protect expensive lenses from potential damage.
The IR-cut filter is a short pass filter that blocks infrared light and transmits the visible; also based on an absorptive glass. The UV-IR cut filter is the combination of a UV cut and a IR cut in one single filter using a UV cut absorptive glass with a thin film layer system as an interference IR cut coating. | |
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Infrared Download Sales Sheet | ||
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Infrared Filters are long-pass filters that block the visible light and pass IR light. They are characterized by their cut-on wavelength, typically the wavelength at which the transmission is 50% of the maximum. These filters use absorptive glasses, that are robust, cost-effective and insensitive to angle of incidence.
In machine vision, one of their typical applications, they are used in front of a lens on a CCD or CMOS camera when the image is to be taken at wavelength in the near infrared. These filters are available unmounted or in mounts with all common thread sizes. | |
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Red and yellow filters Download Sales Sheet | ||
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Red and yellow filters are long-pass filters that pass light at wavelengths longer than their characteristic cut-on wavelength–typically the wavelength at which the transmission is 50% of the maximum. These filters use absorptive glasses, that are robust, cost-effective and insensitive to angle of incidence. In machine vision, one of their typical applications, they are used in front of a lens on a monochrome CCD or CMOS camera to improve image contrast. The appropriate type of filter has to be selected with respect to the color of the object and the type and/or color of the illumination. These filters are available unmounted or in mounts with all common thread sizes. | |
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Green & blue filters Download Sales Sheet | ||
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Green and blue filters are band-pass filters with a specific spectral transmission characteristic that transmits light which is perceived by the human eye as the corresponding color. These filters use absorptive glasses, that are robust, cost-effective and insensitive to angle of incidence.
In machine vision, one of their typical applications, they are used in front of a lens on a monochrome CCD or CMOS camera to improve image contract. The appropriate type of filter has to be selected with respect to the color of the object and the type and/or color of the illumination. These filters are available unmounted or in mounts with all common thread sizes.
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Neutral density filters Download Sales Sheet | ||
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Schneider’s neutral density filters attenuate light by absorption. We are able to offer a wide range of filters with different attenuation levels by carefully controlling the thickness of the filter material. The transmission variations over the visible wavelength range are very small to avoid effects on color balance.
In imaging applications ND filters are used to adjust the intensity to an appropriate level to avoid camera overexposure. If you use a filter instead of stopping down the iris, you will not affect other imaging parameters such as depth of field and diffraction limitations. | |
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Polarizing filters Download Sales Sheet | ||
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Schneider polarizing filters are constructed with dichroic sheets of laminated polymers that are cemented between protective glasses. Natural light and many artificial light sources used for illumination emit unpolarized light or at least light with a low degree of polarization. If light goes through a linear polarizer it will afterwards be linearly polarized in the orientation of the polarization axis of the filter. When using a circular polarizer, light will be either left or right circular polarized. A circular polarizer consists of a linear polarizer combined with a lambda/4 element at an angle of 45°. If a pair of corresponding polarizers is used (linear with linear or circular with circular), light passes when the orientation of their polarization axis is parallel. Light is blocked if the orientation is orthogonal to each other – this means for linear polarizers perpendicular polarization axes and for circular polarizer, left circular combined with right circular (or vice versa). In imaging applications, this effect is used to efficiently suppress reflections on dielectric or metallic surfaces because the reflected light is partially polarized (depending on material and reflective angle) and will be blocked if the filter is rotated in the appropriate orientation. | |
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Interference filters Download Sales Sheet | ||
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In terms of the spectral characteristics there are three basic types of filters:
Band pass filters (BP) that transmit light only around a certain center wavelength.
Standard band pass filters:: BP 565 140 | BP 590 50 | BP 640 110 BP 655 50 | BP 680 100 | BP 855 70 Long pass filters (LP) that transmit light with wavelengths longer than a certain cut-on wavelength. Short pass filters (SP) that transmit light with wavelengths shorter than a certain cut-off wavelength. | |