JP2011058898A - Spectrophotometer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a spectrophotometer for measuring the radiation spectrum of an external light source, which eliminates the need for a dedicated inlet for introducing external light and an optical axis switching mechanism for switching an optical axis. <P>SOLUTION: The spectrophotometer exchangeable of an internal light source is, after removing the internal light source, installed with an external light introduction optical apparatus 4 which is attachable/detachable to/from a light source positioning component (not shown) and includes an external mirror 5 and an internal mirror 6. The external mirror 5 includes an optical axis adjustment axis 7 for directing its mirror surface toward the external light source, thereby performing measurement with the external light source is installed without requiring to attach it to a dedicated holding mechanism. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a spectrophotometer that measures the emissivity or emission spectrum of a heating element such as a heater or a heating furnace, a lighting device such as an LED or an electric lamp.

  The spectrophotometer is an analyzer that irradiates a measurement sample with light and measures an absorption spectrum at each wavelength. The light source of the spectrophotometer uses light of various wavelengths such as X-rays, ultraviolet light, visible light, and infrared light. Among these, the spectrophotometer using infrared light as a light source is converted into a Fourier transform red light. There is an outer spectrophotometer (FTIR).

  In FTIR, an interference wave whose amplitude varies with time is generated by a Michelson interferometer including a fixed mirror and a moving mirror, and this is irradiated onto a sample, and the transmitted light or reflected light is detected as an interferogram. Then, by performing Fourier transform on this, an absorption spectrum is obtained with the wave number on the horizontal axis and the intensity (absorbance or transmittance) on the vertical axis (see, for example, Patent Document 1).

  Infrared spectrophotometers such as FTIR can be used not only to measure the absorption spectrum of a sample, but also to measure the radiation spectrum of heat radiation (infrared radiation) of a heating element such as a heater or a light emitting body such as an electric lamp. . However, it is often difficult to incorporate these heating elements and light emitting bodies as light sources in the spectrophotometer due to problems such as size and temperature (especially with heating elements). Therefore, normally, separately from the spectrophotometer, a holding mechanism for holding the heating element and the light emitter at a predetermined position outside the spectrophotometer, and the heating element and the light emitter (hereinafter referred to as “external light source”) held at the predetermined position. The emission spectrum of the external light source is measured by preparing an external light introducing optical device that introduces light emitted from the external light source into the spectrophotometer.

  An example of the configuration of a conventionally used apparatus for measuring the emissivity or emission spectrum of external light is shown in the schematic top view of FIG. The apparatus includes a spectrophotometer (FTIR) 10, an external light introducing optical device 11 installed adjacent to the side surface of the spectrophotometer 10, and a holding mechanism 12 that holds an external light source 13. .

  In the conventional example of FIG. 5, light (external light) from the external light source 13 passes through the optical system of the external light introducing optical device 11 and enters from the side surface of the spectrophotometer 10. Therefore, in order to introduce external light into the spectrophotometer 10, it is necessary to open a part of the housing side wall of the spectrophotometer 10.

  Further, the spectrophotometer 10 is usually designed so that light emitted from a light source (hereinafter referred to as “internal light source”) accommodated in the apparatus is incident on the interferometer 20. Therefore, in order for the external light introduced into the spectrophotometer 10 to further enter the interferometer 20, it is necessary to appropriately change the optical axis. The spectrophotometer 10 shown in FIG. 5 is designed such that external light introduced from the introduction opening on the side wall of the housing is incident on the interferometer 20 by separately providing an optical axis switching mechanism 22.

  However, in the apparatus of FIG. 5, the optical path to the detector built in the spectrophotometer 10 is blocked by switching the optical axis. Therefore, in this example, the radiation spectrum that has passed through the interferometer 20 and then returned to the external light introduction optical device 11 is detected by using the detector 21 provided in the external light introduction optical device 11. We are measuring.

  FIG. 6 shows another configuration example of an apparatus for measuring the emissivity or emission spectrum of external light. The apparatus shown in this figure is different from that shown in FIG. 5 in that a radiation spectrum can be detected by using a detector built in the spectrophotometer. However, the introduction aperture and the optical axis switching mechanism for introducing external light into the spectrophotometer are the same as in the apparatus of FIG.

JP 2003-14543 A

  As described above, when measuring the emissivity and emission spectrum of an external light source using a spectrophotometer, conventionally, not only an external light introducing optical device and a holding mechanism are separately required, but also in the spectrophotometer itself, An introduction opening for introducing external light into the optical system inside the spectrophotometer and an optical axis switching mechanism for switching the optical axis are required. Moreover, a lid for normally closing the introduction opening is also required. Therefore, there arises a problem that the manufacturing cost of the spectrophotometer increases.

  Further, there is a problem that an optical system used for an infrared spectrophotometer is vulnerable to moisture (humidity). This is due to the fact that optical components such as lenses that transmit infrared light have deliquescence and that infrared light is easily absorbed by moisture, thereby reducing measurement accuracy. For this reason, the optical system inside the spectrophotometer is generally protected by a seal case or the like that prevents moisture from entering. However, in order to introduce external light into the optical system inside the spectrophotometer, it is necessary to open a seal case that protects the optical system together with the housing of the spectrophotometer. If moisture enters through the introduction opening, optical components such as lenses are damaged, and infrared light is absorbed by moisture, resulting in a decrease in measurement accuracy. In addition, the spectrophotometer sometimes eliminates measurement-inhibiting substances such as water vapor by flowing a purge gas through the seal case to perform precise measurement, but there is a seal case that protects the spectrophotometer housing and optical system. If it is opened, the purge gas leaks, so that the purge efficiency is deteriorated.

  Further, when the external light introducing optical device is installed adjacent to the spectrophotometer, there is a problem that the installation area increases. When the installation area is limited, the external light introducing optical device may not be installed. On the other hand, photoconductors such as optical fibers can also be used as external light introducing optical devices in order to solve the problem related to the installation area, but generally photoconductors such as optical fibers are used in specific areas such as infrared light. Since the transmittance is low with respect to the light of the wavelength and a light amount loss occurs, the radiation spectrum may not be measured.

  In addition, when the external light source is a high-temperature heating element, there is a problem that it is dangerous when attached to the holding mechanism.

  The problem to be solved by the present invention is to provide a spectrophotometer that solves these problems.

The spectrophotometer according to the present invention, which has been made to solve the above problems,
In a spectrophotometer having an opening where the internal light source can be replaced,
Positioning means for attaching the internal light source to a predetermined position of a spectrophotometer;
After removing the internal light source, external light introducing means constituted by a reflecting mirror that can be attached to the predetermined position by the positioning means;
It is characterized by providing.

  The opening is preferably provided above the spectrophotometer. Thereby, when an external light introduction means is attached, it can prevent that an installation area increases.

  In addition, the external light introducing means makes an external mirror for introducing external light into the spectrophotometer and the light introduced into the spectrophotometer enter an optical system provided inside the spectrophotometer. And an internal mirror for it.

  Further, the external mirror and / or the internal mirror may be provided with one or a plurality of optical axis adjustment axes for adjusting the optical axis. As a result, the external light can be introduced into the optical system inside the spectrophotometer simply by turning the external mirror toward the external light source and adjusting the optical axis by the optical axis adjustment axis. Therefore, unlike the conventional one, it is possible to measure the installation state as it is without attaching an external light source to a dedicated holding mechanism.

  The spectrophotometer of the present invention is configured to introduce external light from an opening provided in the spectrophotometer for replacing an internal light source. As a result, it is not necessary to provide a separate opening in the seal case protecting the casing of the spectrophotometer and the internal optical system, and parts that block the opening during normal measurement are not necessary. Further, since the same optical axis as that of the internal light source can be used, an optical axis switching mechanism becomes unnecessary. Therefore, the manufacturing cost of the spectrophotometer can be suppressed.

  Further, when the opening is provided above the spectrophotometer, an area for installing the external light introducing means is not required. Further, when the external light introducing means is constituted by two reflecting mirrors, that is, an external mirror and an internal mirror, it is only necessary to point the external mirror in the direction of the external light source, and therefore a dedicated holding mechanism is not necessary. In addition, since the introduction optical system is composed only of a reflecting mirror, there is an advantage that there is no light amount loss unlike a photoconductor such as an optical fiber.

The perspective view which shows the spectrophotometer which has a replaceable internal light source. The perspective view which shows the structure of a light source periphery in the spectrophotometer which has a replaceable internal light source. The perspective view which shows the structure of the light source positioning component periphery after removing an internal light source in the spectrophotometer which has a replaceable internal light source. The perspective view which shows one Example of the spectrophotometer which concerns on this invention. The schematic top view which shows one structural example of the conventional apparatus which measures the radiation spectrum of an external light source. The schematic top view which shows another structural example of the conventional apparatus which measures the radiation spectrum of an external light source.

An embodiment of a spectrophotometer according to the present invention will be described with reference to FIGS.
FIG. 1 is a perspective view showing a spectrophotometer having a replaceable internal light source. In this spectrophotometer, an opening is provided on the upper surface of the housing, and by removing the light source lid 1 covering the opening, it is possible to replace the internal light source mounted inside the housing. Examples of such a spectrophotometer include IRAffinity-1 and IRPrestige-21 manufactured by Shimadzu Corporation. In the spectrophotometer of FIG. 1, since the internal light source is located on the end side, the external light source can be arranged near the spectrophotometer, and the radiant energy can be efficiently introduced into the spectrophotometer. Therefore, it is desirable to use such a spectrophotometer for efficient measurement of the radiation spectrum.

  2 and 3 are perspective views showing the periphery of the internal light source and the light source positioning component (positioning means) after the light source lid 1 is removed. The internal light source 2 in FIG. 2 is fixed at a predetermined position inside the spectrophotometer by the light source positioning component 3 shown in FIG. Thereby, the light emitted from the internal light source 2 is appropriately introduced into the optical system inside the spectrophotometer. The internal light source 2 and the light source positioning component 3 are each designed so that the internal light source 2 can be easily attached and detached without using a tool.

  FIG. 4 is a perspective view showing a configuration around the external light introducing optical device in the spectrophotometer of the present embodiment. The spectrophotometer in this figure is obtained by mounting an external light introducing optical device (external light introducing means) 4 having two reflecting mirrors on the light source positioning component 3 in FIG. The external light introducing optical device 4 is provided with a detachable portion (detachable means) (not shown) at the lower portion of the device so that it can be easily attached to and detached from the light source positioning component 3 without a tool. Each of the two reflecting mirrors is provided with an external mirror 5 for introducing external light into the spectrophotometer and the light introduced by the external mirror 5 inside the spectrophotometer. An internal mirror 6 for entering the optical system. Here, the external mirror 5 includes an optical axis adjusting shaft 7 for directing its mirror surface toward the external light source. By using this optical axis adjusting shaft 7, it is possible to perform measurement in an installed state without attaching an external light source to a dedicated holding mechanism.

  The number of reflecting mirrors used in the external light introducing optical device is not limited to two. For example, if the spectrophotometer is placed directly under the illumination, such as an illumination, if the spectrophotometer is placed directly under the illumination, the optical system inside the spectrophotometer is externally connected with only one reflector. Light can be introduced. Further, by increasing the number of reflecting mirrors and optical axis adjusting axes, it is possible to measure external light sources arranged at various positions without moving the spectrophotometer body.

DESCRIPTION OF SYMBOLS 1 ... Light source cover 2 ... Internal light source 3 ... Light source positioning component 4, 11 ... External light introduction | transduction optical apparatus 5 ... External mirror 6 ... Internal mirror 7 ... Optical axis adjustment axis | shaft 10 ... Spectrophotometer 12 ... Holding mechanism 13 ... External light source 20 ... Interferometer 21 ... Detector 22 ... Optical axis switching mechanism

Claims (5)

In a spectrophotometer having an opening where the internal light source can be replaced,
Positioning means for attaching the internal light source to a predetermined position of a spectrophotometer;
After removing the internal light source, external light introducing means constituted by a reflecting mirror that can be attached to the predetermined position by the positioning means;
A spectrophotometer comprising:   The spectrophotometer according to claim 1, wherein the opening is provided above the spectrophotometer.   The external light introducing means is configured to cause an external mirror for introducing external light into the spectrophotometer and light introduced into the spectrophotometer to enter an optical system provided inside the spectrophotometer. The spectrophotometer according to claim 1, further comprising an internal mirror.   The spectrophotometer according to any one of claims 1 to 3, wherein the external mirror and / or the internal mirror includes one or a plurality of optical axis adjustment axes for adjusting an optical axis. External light introduction optics for introducing external light into the internal optical system for a spectrophotometer having an opening that can replace the internal light source and a positioning means for attaching the internal light source to a predetermined position of the spectrophotometer In the device
Detachable means detachable at a predetermined position of the spectrophotometer by the positioning means;
External light introducing means comprising one or a plurality of reflecting mirrors for introducing external light into an optical system inside the spectrophotometer;
An external light introducing optical device comprising:

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