JPH02150739A - Spectrophotometer - Google Patents

Abstract

PURPOSE:To perform accurate measurement with a spectrophotometer over all wavelength bands by performing transmissivity measurement by using plural mirrors so that the number of optical element arranged sheets at the time of base line correction can become the same as that at the time of measuring an object to be measured. CONSTITUTION:The optical system of this spectrophotometer is provided with a light source 1, spectroscope unit 2 which separates white light into each monochromatic light, toroidal mirror 3 which leads reference light emitted from the unit 2 and sample light to a sample for irradiating the sample with the light, and plane mirror 4. In addition, a holder section 6 for measuring an object to be measured with an optical path difference and the 1st, 2nd, 3rd, and 4th mirrors 7-10 are also provided. At the time of base line correction, the mirror 8 is aligned to the zero point of a scale board 21, with a binocular 25 being removed. Then the binocular 25 which is the object to be measured is set and the position of the mirror 8 is adjusted so that the incident port 22 of the binocular 25 can be irradiated with light without changing positions of the mirrors 7, 9, and 10. When transmissivity of the binocular 25 is measured in such state, reflection losses of each mirror 7-10 can be canceled and only the transmissivity of the binocular 25 can be measured accurately, since the mirrors 7-10 are included as they are in the measuring optical instrument of the binocular 25.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to transmittance measurement of a subject having an optical path difference between incident light and output light, such as a binocular video camera.

[Conventional technology]

As shown in FIG. 1, this type of apparatus includes a method of using a laser light source 30 or the like to move the position of the detector 31 by the relative transmittance at a specific wavelength and an optical path difference each time, and a method of using an optical fiber.

[Problem to be solved by the invention]

The above technology has the disadvantage that continuous transmittance over the entire area cannot be measured because of the laser beam, and in the method of moving the detector 31, the moving distance Q is limited depending on the size of the detector 31, and the signal code of the detector 31 is limited. There were drawbacks from a stability standpoint, such as the generation of noise due to the length and poor reproduction of the light-receiving surface due to the movement of the detector.

An object of the present invention is to make it possible to measure the transmittance using the same optical element and under the same conditions as when baseline correcting the transmittance of an object having an arbitrary optical path difference.

[Means to solve the problem]

For the above purpose, as shown in FIG. 2, a plurality of mirrors 7 to 8 are used to construct an Ω-shaped optical system to perform baseline correction. When measuring the object 13, the mirror 8 on the incident side of the object 13 is moved as shown in FIG.

Incident light enters the subject 13. At this time, the exit side of the subject is aligned with the position of the mirror 9 during baseline correction.

In the reverse method, as shown in FIG. 4, the mirror 9 on the output side of the subject 13 is moved to match the output light. In this case, the incident side of the subject may be aligned with the position of the mirror 8 during baseline correction.

By configuring the optical system for measuring the object in this way, it is possible to accurately measure the transmittance of the object having an optical path difference.

[Effect]

Since the movable mirrors can be moved to arbitrary positions according to the optical path difference of the object, the transmittance of the object can be measured no matter how large the optical path difference of the object is.

〔Example〕

An embodiment of the present invention will be described below with reference to FIGS. 5 to 7. Fig. 5 shows an optical system diagram of the device implementing the present invention, in which 1 shows the light source, 2 shows the spectrometer that separates white light into monochromatic light, and 3 shows the control light and sample light emitted from the spectrometer. 4 is a plane mirror, 6 is a holder part for measuring a subject having an optical path difference according to the present invention, 7 is a first mirror, 8 is a second mirror, 9 is a third mirror, and 4 is a plane mirror. The mirror 10 is the fourth mirror, and the first mirror 7 is movable. Note that FIG. 5 shows the optical system during baseline correction. Reference numeral 11 is an integrating sphere, and 12 is a white plate compression-molded from Wi aluminum for scattering light. 26 is a detector and integrating sphere 11
It is attached to a part of the integrating sphere 11 and converts the light that is reversed within the integrating sphere 11 into an electrical signal.

Figure 6 is Sou II! This is an example of application to a mirror transmittance measuring device, and the same parts as in FIG. 5 are given the same symbols.

Reference numerals 14 and 16 are guides for moving the mirror holder 15 to which the mirror 8 is attached, and the guide 16 has a scale 21 so that the amount of movement can be measured.

A mirror holder 17 holds a mirror, and a mirror holder 18 holds a mirror 9. Although these mirror holders are used as fixed mirror holders in this embodiment, they can also be moved like the mirror holder 15.

19 is a mirror holder to which mirror 1o is attached.

20 is a condensing lens that condenses the light from the mirror 10 to an integrating sphere 11
The white board 12 is irradiated with light.

With such a configuration, binoculars having an optical path difference can be measured using the following procedure.

At the time of baseline correction, the mirror 8 is set to the 0 point on the scale plate 21, and the correction is performed in the state of the optical system shown in FIG.

At this time, the binoculars 25 that are the object to be examined are removed.

Next, attach the twin rfA mirrors without changing the positions of mirrors 7, 9, and 10, and adjust the position of mirror 8 so that the light irradiates the entrance port 22 of the twin II mirror 25, which is the object to be inspected. .

When measuring the transmittance in this state, the mirrors 7.8 and 9.10 during baseline correction are directly in the measurement optical path of the binoculars 25, which is the subject, so the reflection loss due to each mirror is canceled and the transmittance of only the binoculars is can be measured accurately and with good stability.

〔Effect of the invention〕

According to the present invention, there is an effect that the transmittance of a subject having an optical path difference between the incident and the output can be measured stably and accurately in the entire wavelength range of the spectrometer.

[Brief explanation of the drawing]

Fig. 1 is a diagram showing a conventional device, Fig. 2 is a system diagram of the basic optical system of the present invention during baseline correction, Fig. 3 is a measurement optical system diagram for a subject with an optical path difference, and Fig. 4 is a system diagram of the basic optical system of the present invention during baseline correction. 5 is an optical system diagram of an embodiment of the present invention; FIG. 6 is a plan view of an embodiment of the present invention; FIG. FIG. 7.8,9.10...mirror, 11...integrating sphere, 1
3... Subject, 14.16... Guide, 21...
Scale, 25... Binoculars, 26... Detector. Cause diagram Figure 4

Claims (1)

[Claims] 1. In a device that measures transmittance by irradiating a subject with an optical path difference with a variable monochromatic light spectrum, a plurality of mirrors are used to adjust the optical elements during baseline correction and measurement of the subject. A spectrophotometer characterized by being able to measure transmittance by arranging the same number of panels. 2. The spectrophotometer according to claim 1, characterized in that the position of the array mirror can be arbitrarily varied according to the optical path difference of the subject.