JPH09222358A - Array of spectral detecting element - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable a miniaturization and improvement in accuracy by forming spectral filter membranes which continuously differ in a spectrum characteristic along the row of light-receiving elements on the surface of a light detecting element array. SOLUTION: N pieces of light-receiving elements 12 are installed on the surface of a substrate 11 at regular intervals and which forms a light-receiving element array. In addition, N pieces of spectral filter membranes 13 each of which has a different spectral characteristic are installed on each surface of the light-receiving elements 12. These spectral filter membranes 13 are directly formed on the light-receiving element 12 by a membrane forming process like vapour deposition. Therefore the array is made compact, lightweight, simplified and improved in accuracy and as the spectral filter membranes 13 do not fall off the light-receiving element 12, its reliability is improved as well. In addition, the spectral filter membranes 13 have the characteristic that the transmitted wavelength of its part according to the N pieces of light-receiving elements 12 changes at regular intervals.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a spectral detector array having a plurality of different spectral characteristics.

[0002]

2. Description of the Related Art As a conventional photodetector, for example, (1) JP-A-3-231475 and (2) JP-A-61-99027 are disclosed.

In the above (1), there is proposed a photo-detecting element in which a film for separating light of a specific wavelength is formed on the light-receiving surface of the photo-detecting section for converting an optical signal into an electric signal. In addition, FIG. 4 shows the configuration of (2) above, in which a plate-like spectrum whose transmission wavelength is sequentially changed in the arrangement direction of the light receiving element array 1 is arranged on the light receiving element array 1 in which a large number of light receiving elements are arranged in one row. The filter 2 is mechanically arranged and assembled, and the plate-like spectral filter 2
A spectrophotometric device has been proposed in which the slit plate 3 is mechanically arranged and assembled.

[0004]

However, in the above (1), since the film that disperses the light of the specific wavelength is only formed on the photodetector, the light of a plurality of different wavelengths is detected. In order to do so, it is necessary to manufacture a plurality of photodetector elements having individual spectral characteristics and arrange them mechanically.In such a configuration, the accuracy of the detection wavelength is limited by the mechanical arrangement accuracy of the photodetector elements. There is a problem that is done.

In the above (2), the light receiving element array 1
Since light having a plurality of different wavelengths is detected by mechanically assembling the plate-shaped spectral filter 2, a space for housing the spectral filter 2 is required, and the device becomes large, heavy, complicated, and accurate. There is a problem that it gets worse. Furthermore, the mounting position of the spectral filter 2 changes due to environmental conditions such as vibration after manufacture and changes in temperature environment, and as a result, the measurement accuracy deteriorates, or in the worst case, the spectral filter 2 falls off to function. There is a problem that it may be lost.

In view of the above conventional problems, it is an object of the present invention to provide a spectroscopic detection element array which can be reduced in size, weight, simplification, accuracy, and reliability.

[0007]

In order to achieve the above object, the present invention is provided on the surface of a photodetector array in which a plurality of light receiving elements for converting an optical signal into an electric signal are arrayed, in the array direction of the light receiving elements. Aspects of the invention are characterized in that a spectral filter film having continuously different spectral characteristics is formed along the line.

Further, the spectral filter film is characterized in that the transmission wavelengths of portions corresponding to the plurality of light receiving elements change at equal intervals.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a side sectional view showing an embodiment of a spectroscopic detection element array according to the present invention, FIG. 2 is an explanatory view showing an example of the relationship between the characteristics of the spectroscopic filter film of FIG. 1 and the output of the photodetection element, FIG. FIG. 6 is an explanatory diagram showing another example of the relationship between the characteristics of the spectral filter film of FIG. 1 and the output of the photodetector.

In FIG. 1, a plurality of (N) light receiving elements 12 are mounted in a row at equal intervals on the surface of a substrate 11 to form a light receiving element array, and further, on each surface of the light receiving elements 12. Are formed with N spectral filter films 13 having different spectral characteristics. In this case, the spectral filter film 13 is directly formed on the light receiving element 12 by a film forming process such as vapor deposition, and therefore, it is possible to achieve size reduction, weight reduction, simplification, and improvement in accuracy. 1
Since it is not peeled off from No. 2, the reliability can be improved.

In such a configuration, when the transmission wavelengths of the N spectral filter films 13 become proportionally (at equal intervals) from the first to the Nth, as shown in FIG. 2A. , Output at equal intervals with respect to the wavelength is obtained as shown in FIG. Further, when the transmission wavelength of the spectral filter film 13 becomes longer from the first to the Nth at unequal intervals as shown in FIG. 3A, the wavelength becomes as shown in FIG. 2B. In contrast, unequally spaced outputs are obtained.

[0012]

As described above, according to the present invention, since a spectral filter film having continuously different spectral characteristics is formed on the surface of the photodetector array along the arrangement direction of the light receiving elements, it is possible to reduce the size, It is possible to achieve weight reduction, simplification, improvement in accuracy, and improvement in reliability.

[Brief description of drawings]

FIG. 1 is a side sectional view showing an embodiment of a spectroscopic detection element array according to the present invention.

FIG. 2 is an explanatory diagram showing an example of the relationship between the characteristics of the spectral filter film of FIG. 1 and the output of its photodetector.

FIG. 3 is an explanatory diagram showing another example of the relationship between the characteristics of the spectral filter film of FIG. 1 and the output of the photodetector.

FIG. 4 is an exploded perspective view showing a conventional spectral detection element array.

[Explanation of symbols]

 11 substrate 12 light receiving element 13 spectral filter film

Claims (2)

[Claims] 1. A spectral filter film having continuously different spectral characteristics along the array direction of the light receiving elements is formed on the surface of a photodetector array in which a plurality of light receiving elements for converting an optical signal into an electric signal are arrayed. Spectral detector array. 2. The spectral detection element array according to claim 1, wherein the transmission wavelengths of portions of the spectral filter film corresponding to the plurality of light receiving elements change at equal intervals.