JPH0594801U - Composite optical filter - Google Patents

Abstract

(57) [Summary] [Object] To obtain a composite optical filter having a structure in which an optical filter having any desired spectral characteristic can be easily obtained in a short time. [Structure] A plurality of vapor-deposited films are formed on a glass substrate to prepare an optical filter having a single spectral characteristic, and a plurality of optical filters having the single spectral characteristic are combined and laminated to form a combination of the single spectral characteristics. To obtain desired spectral characteristics.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an optical filter used in various optical measuring instruments and the like, and proposes a composite optical filter having a structure capable of easily obtaining desired spectral characteristics.

[0002]

[Prior Art]

 Depending on the purpose of use, the optical filter has a bandpass characteristic of transmitting only light of a specific wavelength, a highpass characteristic of transmitting light of a wavelength shorter than a specific wavelength, and a light of wavelength longer than a specific wavelength. Various spectral characteristics such as low-pass characteristics are required.

Conventionally, in order to obtain these various characteristics, a vapor deposition film is deposited on a glass substrate over a plurality of layers, and various spectral characteristics are obtained according to the type and combination of vapor deposition films.

[0004]

[Problems to be solved by the device]

 Among the spectral characteristics, the high-pass characteristic and the low-pass characteristic are single characteristics and can be made relatively easily. On the other hand, making an optical filter with bandpass characteristics has the drawback of being laborious. That is, the bandpass characteristic is created by combining the highpass characteristic and the lowpass characteristic. Therefore, the number of vapor-deposited films of the optical filter having the bandpass characteristic is about twice that of the highpass characteristic and the lowpass characteristic. Therefore, an optical filter having a band-pass characteristic has a drawback that it takes time to manufacture.

In reality, however, the wavelength to be transmitted varies depending on the purpose of measurement and the like, and therefore an optical filter having the required spectral characteristics must be made each time. As a result, there is a drawback in that an optical filter with each spectral characteristic must be made over time.

[0006]

[Means for Solving the Problems]

 In the present invention, a single optical filter having a single spectral characteristic is prepared in advance, and these single optical filters are selected and laminated as necessary to form a composite optical filter having a desired spectral characteristic. It is a thing. Therefore, according to this invention, a composite optical filter having a desired spectral characteristic can be obtained only by laminating and combining a plurality of single optical filters, so that an optical filter having a desired spectral characteristic can be produced in a short time. ..

[0007]

【Example】

 FIG. 1 shows an embodiment of this invention. Reference numerals 10 and 20 in the figure each denote a single optical filter having a single spectral characteristic. Each of these single optical filters 10 and 20 is composed of glass substrates 11 and 21, and vapor-deposited films 12 and 22 of a plurality of layers are formed on the glass substrates 11 and 21, respectively. In this example, the vapor-deposited films 12 and 22 are faced to each other, and an optical adhesive 30 having a known refractive index is interposed therebetween to laminate the single optical filters 10 and 20. If the adhesive 30 is preferably a UV adhesive having a refractive index close to that of air, an optical filter having characteristics in which the characteristics of the single optical filters 10 and 20 are directly superimposed can be obtained.

When the single optical filters 10 and 20 have a high-pass characteristic A and a low-pass characteristic B as shown by curves A and B in FIG. 2, for example, these high-pass characteristic A and low-pass characteristic B are used. The wavelength λ determined by the intersection of the characteristics B. An optical filter having a bandpass characteristic C centered at is obtained. Further, as shown in FIG. 3, by combining the high-pass characteristic D and the low-pass characteristic E, the band-pass characteristic F having a relatively wide pass band can be obtained.

[0009]

[Effect of the device]

 As described above, according to this invention, various single optical filters having a single spectral characteristic are prepared, and the single optical filters are combined and laminated to obtain a desired spectral characteristic. Therefore, there is an advantage that an optical filter having the required spectral characteristics can be easily obtained in a short time, and the effect is great for practical use.

In addition, when two sets of single optical filters are laminated and combined as shown in the above-mentioned embodiment, when the evaporation films 12 and 22 are faced and combined, the evaporation films 12 and 2 2 Can have a structure that does not come into contact with air. As a result, it is possible to avoid the inconvenience that the vapor deposition films 12 and 22 adsorb moisture and the spectral characteristics change.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of the present invention.

FIG. 2 is a graph for explaining the spectral characteristics of the optical filter according to the present invention.

FIG. 3 is a graph similar to FIG.

[Explanation of symbols]

 10,20 Single optical filter 11,21 Glass substrate 12,22 Deposition film 30 Adhesive

Claims (1)

[Scope of utility model registration request] 1. A composite optical filter comprising a plurality of single optical filters having different spectral characteristics laminated and combined to form an optical filter having desired spectral characteristics.