JPH0316058Y2 - - Google Patents

Description

[Detailed description of the invention] <Industrial field of application> This invention relates to a photometric device, and more specifically, by irradiating a sample with light from a light source,
The present invention relates to a photometric device that can measure reflected light or transmitted light (hereinafter referred to as "light from a sample").

<Conventional technology> Conventionally, in photometers that use a lens system to converge light from a sample, the diameter of the lens is limited, so the aperture angle cannot be increased, and the amount of received light is limited. There was a problem in that the photometry accuracy could not be improved because of the smaller size. Therefore, in order to solve this problem, an apparatus has been provided which performs photometry by irradiating a sample with light, causing the light from the sample to be received by an optical fiber, and guiding it to a detection section.

The specific configuration of such a device takes into account that the size of the sample varies widely from standard size to minute size.
An optical fiber drive mechanism is provided to change the distance between the light-receiving surface of the optical fiber and the sample. This allows the distance to be changed in accordance with the sample size, thereby changing the light-receiving area so that only light from the sample is received.

<Problems to be Solved by the Invention> In the photometric device having the above structure, there is a problem in that the measuring head becomes large because the light receiving section and the light projecting section constituting the measuring head have an integral structure. In particular, in the case of the integrating sphere method, which is said to be the closest to natural illumination, the size is usually 150φ in order to reduce the aperture ratio.

The reason why miniaturization is not possible is that it is necessary to install a drive mechanism to move the optical fiber as mentioned above, and the allowable bending radius of the optical fiber is smaller than that of a fixed type. One example is that the case is larger.

In addition, since the optical fiber is movable, when vibrations are applied from the outside, the flexible part of the optical fiber vibrates, changing the amount of light.
There is also the problem that accurate photometry cannot be performed because the light-receiving surface is displaced from the position directly facing the sample.

This idea was made in view of the above problems, and it is possible to reduce the overall size, to perform accurate photometry corresponding to the size of the sample, and to avoid the negative effects of vibration. The purpose of the present invention is to provide a photometric device that can solve this problem.

<Means for solving the problem> In order to achieve the above object, the photometric device of this invention is equipped with an optical fiber that receives the light from the sample and guides it to the outside. During measurement, it is placed so as to maintain a certain distance from the sample, and a light shielding member is attached to the light output side of the optical fiber to concentrically regulate the aperture angle of the optical fiber, and the light passing through the light shielding member is input. A detection unit is installed to detect the light intensity from the sample.

However, it is preferable that the light shielding member is capable of adjusting the aperture angle of the optical fiber, and the light projecting section further includes an optical fiber that guides monitor light for light source compensation. preferable.

Further, it is preferable that a mask member for regulating the photometric portion of the sample is attached so as to face the light receiving surface of the optical fiber.

<Operation> With the photometry device having the above configuration, the light from the light projecting section is irradiated onto the sample, the light from the sample is guided by the optical fiber, and a part of the light led out from the light output side is spread out in concentric circles. The reflected light intensity can be detected by irradiating the detection unit with the light shielded by a light shielding member that regulates the aperture angle.

In addition, if the aperture angle of the optical fiber can be adjusted using the light shielding member, even if the size of the sample changes, the optical fiber will not need to be moved and the reflected light from parts other than the sample can be adjusted. This is preferable because it allows accurate photometry to be performed by eliminating the influence of This is preferable because it allows accurate photometry.

Furthermore, if the mask member for regulating the photometric portion of the sample is installed facing the light-receiving surface of the optical fiber, the aperture ratio of the integrating sphere, etc. can be reduced and the S/N ratio can be improved. This is preferable because it can be done.

<Example> Hereinafter, an example will be described in detail with reference to the accompanying drawings.

The drawing is a simplified diagram showing one embodiment of a photometric device, and includes an integrating sphere 1 as a light projecting part and a visible light emitter 2.
and a spectrophotometric device 3 as a detection section.

To explain in more detail, the integrating sphere 1 has a barium sulfate layer 1 on its inner surface to efficiently diffuse incident light.
1 is formed, and the sample S is placed at a predetermined position on the integrating sphere 1.
A sample window 12 is formed to face the inside, and a visible light introduction window 13 is formed at a predetermined position not directly facing the sample window 12 to introduce the irradiated light from the visible light emitter 2. 12
An optical fiber 14 for photometry that efficiently receives the reflected light from the sample S is installed almost directly facing the sample window 12, and an optical fiber 15 for light source compensation is installed at a predetermined position that does not directly face the sample window 12. There is. Note that 16 is a mask member attached at a predetermined position between the sample window 12 and the sample S, and has a hole of a size corresponding to the measurement area.

The visible light emitter 2 is composed of an incandescent light bulb or the like, and is attached to the center of a concave mirror 21 for condensing light. A light source chromaticity conversion filter 22 and a cut filter 23 are installed between the visible light emitter 2 and the visible light introducing window 13, and a mirror 24 that guides the light from the visible light emitter 2 to the visible light introducing window 13 is installed. The above-mentioned cut filter 23 is capable of cutting light with a wavelength below a predetermined value. For example, if it is a cut filter for fluorescence measurement, it usually cuts out light with a wavelength of 400 nm or less, 450 nm or less, 500 nm or less, or 550 nm or less. A material that can block light is used.

The spectrophotometer 3 includes an optical fiber 14,
The light received by the optical fiber 15 is selectively guided to a spectroscopic optical system to obtain a light intensity distribution for each wavelength, and the reflected light from the sample S guided by the optical fiber 14 is The grating 36 is irradiated with light through the lens 31, a plate-shaped light shielding member 40 with a round hole formed in the center, the mirror 32, the half mirror 33, the slit 34, and the mirror 35, and the grating 36 emits light for each wavelength. The reflected light intensity of the sample S is measured by spectroscopy and reception by the photodiode array 37.
Note that the light shielding member 40 is arranged so that the center of the round hole of the light shielding member 40 intersects with the optical axis. On the other hand, the monitor light guided by the optical fiber 15 is passed through the lens 38, the half mirror 33, and the slit 3.
4, and grating 3 via mirror 35
6, the light is separated into wavelengths by a grating 36, and is received by a photodiode array 37, thereby measuring the intensity of the monitor light. In addition, 39 is an optical fiber 14,1
This is a switching rotary plate that selectively transmits light from 5.

With the photometer having the above configuration, after setting the sample S in the sample window 12 of the integrating sphere 1, by applying a voltage to the visible light emitter 2, the sample S can be irradiated with diffused light. , reflected light from the sample S can be guided to the spectrophotometer 3 via the optical fiber 14. Further, diffused light from a portion other than the portion where the sample S is attached can be guided to the spectrophotometer 3 via the optical fiber 15.

And the optical fibers 14, 15
The light guided by is selectively transmitted by the switching rotary plate 39 and guided to the optical system.

Among the above two lights, the reflected light from the sample S is converged by the lens 31, and a part of the light is concentrically blocked by the light shielding member 40, so that the exposed area of the sample S corresponding to the mask member 16 is Only the light of the corresponding portion is transmitted, and the reflected light intensity is determined by irradiating the grating 36 through the mirror 32, half mirror 33, slit 34, and mirror 35 to separate the lights, and receiving the light by the diode array 37. can be measured.

On the other hand, regarding the monitor light, the lens 38, half mirror 33, slit 34, and mirror 3
The diffused light intensity can be measured by irradiating the light onto the grating 36 through the diode array 37 and receiving it at the diode array 37.
Changes in diffused light caused by dirt or the like on the barium sulfate layer 11 can be detected.

Therefore, by correcting the intensity of the reflected light from the sample S based on the change in the diffused light detected by the diffused light intensity measurement, the colorimetry of the sample S can be performed accurately.

In addition, the sample S using the optical fiber 14
If the light receiving range changes, the light shielding member 40 can be replaced with one having a hole large enough to transmit only the light in the range corresponding to the light receiving range, allowing accurate colorimetry. can be done.

Therefore, it is possible to reduce the aperture ratio, increase brightness, and improve photometric accuracy.

Note that this invention is not limited to the above embodiments, and for example, by using a light shielding member 40 that can change the light transmission range, that is, the diameter of the round hole, it is possible to reduce the trouble of replacing the light shielding member. It is omitted that the light shielding member 40 is arranged at a position that is similar to the light emitting surface of the optical fiber 14 and the grating 3.
6 (for example, the position between the switching rotary plate 39 and the lens 31). In addition, by omitting the grating 36, only scattering can be measured. By intervening a sample such as a filter or the like, it is possible to measure absorbance, etc., and various other design changes can be made without changing the gist of this invention.

<Effects of the invention> As described above, in this invention, the optical fiber is fixedly attached in the light projecting section, and a light shielding member for regulating the aperture angle is attached at the output end face of the optical fiber. It has the unique practical effects of being able to be miniaturized, allowing accurate photometry to be performed without being affected by external vibrations, and being able to easily adapt to the size of the sample.

[Brief explanation of the drawing]

The drawing is a schematic diagram showing one embodiment of a photometric device. 1... Integrating sphere as a light projecting section, 2... Visible light emitter, 3... Spectrophotometer as a detection section, 14,
15... Optical fiber, 16... Mask member, 40... Light shielding member, S... Sample.

Claims (1)

[Scope of Claim for Utility Model Registration] 1. A device that measures a sample by irradiating the sample with light from a light projecting section and receiving light from the sample, which receives light from the sample and guides it to the outside. The light-receiving surface of the optical fiber is placed so as to maintain a certain distance from the sample during measurement, and a light-shielding member is installed on the light-exiting side of the optical fiber to concentrically regulate the aperture angle of the optical fiber. A photometric device characterized by being equipped with a detection section that receives light that has passed through a member and detects light intensity from a sample. 2. The photometric device according to claim 1, wherein the light shielding member is capable of adjusting the aperture angle of the optical fiber. 3. The photometric device according to claim 1, wherein the light projecting section has an optical fiber that guides monitor light for light source compensation. 4. The photometric device according to claim 1 of the above-mentioned utility model registration, wherein a mask member for regulating the photometric portion of the sample is attached to face the light-receiving surface of the optical fiber.