CN201285457Y - An optical filter - Google Patents

Abstract

The utility model relates to an optical filter which is formed by splicing two wedge-shaped optical filters, wherein two wedge-shaped surfaces of the wedge-shaped optical filters are corresponding, are plated with films and are used for demarcating the spectrum transmission ratio of various high- precision optical instruments. The two wedge-shaped surfaces are plated with the films, reflected light deviates an incidence light path direction to avoid the exploration influence caused by many times of reflection between the reflected light and a window, and a transmission radio value transmitted by the optical filter has little influence by the optical structure of a demarcating instrument and a detected instrument.

Description

a filter

technical field

The utility model relates to an optical filter for calibrating the spectral transmittance of various high-precision optical instruments, in particular to a wedge-shaped optical filter suitable for optical instruments with different structures.

Background technique

The structure of the currently known optical filter is composed of a glass sheet with isotropy and uniform thickness. When a certain luminous flux is incident on the surface of the filter, part of the luminous flux will be transmitted due to the spectral transmission and reflection characteristics of the glass sheet. The ratio of the transmitted luminous flux to the incident total luminous flux is the transmittance of the filter. After the transmittance is calibrated with high precision, it can be applied to the calibration and verification of various spectral transmittance instruments. However, calibrating the instrument's transmittance reading against this value is dependent on the optical configuration of the calibrating instrument and the instrument being calibrated. When the construction of the two types of instruments is inconsistent, it will lead to data deviation. The main reason is that part of the instrument sample compartment window is parallel to the measured filter, resulting in multiple reflections between the sample reflected light and the window, and this part of the reflected light will enter the detection optical path again, resulting in a larger value.

Utility model content

The purpose of the utility model is to provide an optical filter to solve the problem in the prior art that data deviation occurs due to the inconsistency of the structures of the two types of instruments during calibration.

In order to achieve the above object, the technical solution of the utility model is to adopt a kind of optical filter, and the optical filter is spliced by two wedge-shaped optical filters, wherein the two wedge surfaces of the wedge-shaped optical filter are opposite, and the wedge surfaces coated with film.

Wherein, the two wedge-shaped filters are spliced into a rectangular shape.

Wherein, the optical filter is made of high-purity quartz material.

The advantages and beneficial effects of the utility model lie in that the transmittance value transmitted by the optical filter is minimally affected by the optical structure of the calibration instrument and the instrument to be tested.

Description of drawings

Fig. 1 is the schematic diagram of the light path of the utility model.

In the figure: 1. Wedge filter; 2. Wedge filter; 3. Incident luminous flux; 4. Reflected luminous flux; 5. Outgoing luminous flux; a, surface A; b, wedge surface.

Detailed ways

The following examples are used to illustrate the utility model, but not to limit the scope of the utility model.

As shown in Figure 1, the filter of the utility model is formed by splicing a wedge-shaped filter 1 and a wedge-shaped filter 2 into a rectangular shape to ensure that it can be installed on a standard filter bracket, wherein the two wedge-shaped filters The wedge surfaces are opposite, and films are coated on the two wedge surfaces, and the luminous flux passing through the filter is controlled by the material and thickness of the film.

During calibration, the incident luminous flux 3 will pass through the two surfaces of the wedge-shaped filter in turn. Since the spectral transmittance of quartz is very high and the surface reflection is very low, the luminous flux reflected by A surface a can be completely ignored after multiple reflections. When reaching the wedge surface b, the incident luminous flux 3 will be decomposed into reflected luminous flux 4 and outgoing luminous flux 5, but it can be seen from Fig. There are multiple reflections between the chips, so it does not have any influence on the detection.

The beneficial effect of the utility model is that the transmittance value transmitted by the optical filter is minimally affected by the optical structure of the calibration instrument and the instrument to be tested.

The above is only the preferred embodiment of the utility model, and it should be pointed out that for those of ordinary skill in the art, without departing from the technical principle of the utility model, some improvements and modifications can also be made. And retouching should also be regarded as the protection scope of the present utility model.

Claims (3)

1. An optical filter, characterized in that the optical filter is spliced by two wedge-shaped filters, wherein the two wedge surfaces of the wedge-shaped optical filter are opposite to each other, and the wedge surfaces are coated with a film. 2. The optical filter according to claim 1, wherein the two wedge-shaped optical filters are spliced into a rectangular shape. 3. The optical filter according to claim 1, characterized in that the optical filter is made of high-purity quartz material.

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