Notice on Customized Filter
Customized filter is a type of filter/filter formed by coating a series of film layers of different dielectric materials between glass substrates according to customer needs when standard filters do not meet usage requirements. When multiple wavelengths of mixed light pass through the filter, interference effects occur due to different refractive indices, resulting in specific wavelengths of light having very high transmittance while other wavelengths of light are reflected or absorbed. Customized filters are usually ordered in one batch, rather than single piece filters. Ruicheng Optoelectronics provides customized services for various types of filters.
Precautions for customizing filters
Firstly, it is necessary to consider two quantities: the incident angle Aol and the cone angle cone Angle. The incident angle is the angle at which light is incident, for example, in a dichroic mirror, it is usually 45 degrees. The cone angle is the angle between the edge ray and the center ray due to focusing or diverging, and is sometimes expressed as a half cone angle. The changes in incident angle and cone angle have a significant impact on the spectral curve of the filter. Increasing the incident angle may cause the filter curve to shift, while the cone angle may reduce the transmission area of the dichroic mirror.
Secondly, it is necessary to consider the polarization of light. According to the Fresnel polarization formula, when light propagates at the interface between two substances, the reflectivity and transmittance are related to the polarization state of the light. Therefore, users must specify the polarization of the light when customizing. If the incident angle of the customized filter exceeds 20 degrees; The polarization state (s, p, or average) must be indicated to ensure that the final filter meets the requirements.
How to determine if a customized filter is a qualified product? We will start from the following aspects.
1、 When the scratch level of the filter exceeds the required scratch level on the surface, it is directly unqualified.
2、 The scratch series of customized filters should not exceed the series required for surface quality, but when there are the largest scratches in the filter, even the total sum of the largest scratches should not exceed 1/4 of the direct length of the filter.
3、 When there is a maximum scratch in the filter and the maximum scratch does not exceed 1≤ 4D, the sum of the scratch length multiplied by the ratio of the scratch length to the filter diameter should not exceed half of the maximum scratch count.
4、 When the scratch series of the customized filter does not exceed the required surface quality series and there are no maximum scratches in the filter, the sum of the scratch series multiplied by the scratch length of all products and the filter diameter shall not exceed the maximum scratch sequence.
5、 When the quality index of the filter requires a scratch level of 20 or higher, there should be no dense scratches on the surface of the filter, that is to say, no four or more scratches of 10 are allowed in any area of the filter element 6.35mm.
For moisture resistance or ease of installation, Ruicheng photoelectric filters are vacuum packaged.
Precautions for customizing filters
Firstly, it is necessary to consider two quantities: the incident angle Aol and the cone angle cone Angle. The incident angle is the angle at which light is incident, for example, in a dichroic mirror, it is usually 45 degrees. The cone angle is the angle between the edge ray and the center ray due to focusing or diverging, and is sometimes expressed as a half cone angle. The changes in incident angle and cone angle have a significant impact on the spectral curve of the filter. Increasing the incident angle may cause the filter curve to shift, while the cone angle may reduce the transmission area of the dichroic mirror.
Secondly, it is necessary to consider the polarization of light. According to the Fresnel polarization formula, when light propagates at the interface between two substances, the reflectivity and transmittance are related to the polarization state of the light. Therefore, users must specify the polarization of the light when customizing. If the incident angle of the customized filter exceeds 20 degrees; The polarization state (s, p, or average) must be indicated to ensure that the final filter meets the requirements.
How to determine if a customized filter is a qualified product? We will start from the following aspects.
1、 When the scratch level of the filter exceeds the required scratch level on the surface, it is directly unqualified.
2、 The scratch series of customized filters should not exceed the series required for surface quality, but when there are the largest scratches in the filter, even the total sum of the largest scratches should not exceed 1/4 of the direct length of the filter.
3、 When there is a maximum scratch in the filter and the maximum scratch does not exceed 1≤ 4D, the sum of the scratch length multiplied by the ratio of the scratch length to the filter diameter should not exceed half of the maximum scratch count.
4、 When the scratch series of the customized filter does not exceed the required surface quality series and there are no maximum scratches in the filter, the sum of the scratch series multiplied by the scratch length of all products and the filter diameter shall not exceed the maximum scratch sequence.
5、 When the quality index of the filter requires a scratch level of 20 or higher, there should be no dense scratches on the surface of the filter, that is to say, no four or more scratches of 10 are allowed in any area of the filter element 6.35mm.
For moisture resistance or ease of installation, Ruicheng photoelectric filters are vacuum packaged.