CN113237831A

CN113237831A - Uniform light source generating device for short-wave infrared imaging spectrum system

Info

Publication number: CN113237831A
Application number: CN202110557565.XA
Authority: CN
Inventors: 朱严; 何绵雨; 杜文武; 王超; 李朝阳
Original assignee: Anhui Specreation Instrument Science & Technology Co ltd
Current assignee: Anhui Specreation Instrument Science & Technology Co ltd
Priority date: 2021-05-21
Filing date: 2021-05-21
Publication date: 2021-08-10

Abstract

The invention belongs to the field of optical instruments, and particularly relates to a generation device of a short-wave infrared uniform light source. In the scheme, the same number of point light sources can be obtained at the light-emitting end of the optical fiber bundle set according to the specific number of the optical fiber bundle set, so that the preliminary homogenization of the light sources is realized, and the light sources are further homogenized by the difference of the areas and the positions of the same optical fiber bundle at the light-emitting end and the incident end, so that a uniform light source with uniform illumination and brightness meeting the requirements is provided for the linear Fresnel lens.

Description

Uniform light source generating device for short-wave infrared imaging spectrum system

Technical Field

The invention belongs to the field of optical instruments, and particularly relates to a generating device of a short-wave infrared uniform light source.

Background

For a mineral sample, specific components of the mineral sample have strong absorption effect on light waves under specific wavelengths, so the component composition of the mineral can be rapidly detected by measuring the intensity of the light waves under each wavelength of reflected light of the sample, namely the principle of measuring the mineral components by an imaging spectrum system. For the rapid detection of the mineral components in the field, the imaging spectrum system is the best detection instrument. Aiming at the component characteristics and the spectral absorption characteristics of minerals, the wavelength of a light source required in the detection process is in the range of 900-1700 nm, namely short-wave infrared light. As mentioned above, since the principle of the imaging spectroscopy system is to measure the absorption intensity of a sample to light waves, a light source needs to be uniformly irradiated on the sample, otherwise, a large measurement error occurs; meanwhile, a larger light source intensity is required, otherwise, insufficient light intensity received by the imaging spectrum measurement system will also increase measurement errors.

Therefore, a uniform short-wave infrared light source with enough intensity is a basic premise for improving the detection precision. There are many different methods for obtaining a uniform light source. Most commonly, a plurality of point-like light sources with small size are used to form a uniform light source in a certain spatial arrangement manner, or a plurality of lens structures are combined to further improve the uniformity of the light source, but such a method is structurally complicated and occupies a large space when being arranged, and meanwhile, the available point-like light sources are required. In addition, there is a method using an integrating sphere, which is technically mature but limited by a structure that generates a limited light source size, and also has a large light loss and a large limitation in output light intensity. Furthermore, the uniformity of the light source is improved by the light guide plate, but the light source has low brightness and limited use scenes. Aiming at the requirements of light source wavelength and light intensity in mineral detection, no available uniform light source product or small-size point light source exists in the market at present, and only a halogen tungsten lamp light source with larger size can be selected. Due to the size limitation of the imaging spectrum system, a sufficient number of halogen tungsten lamp light sources cannot be arranged to increase the uniformity of the light sources, and the light intensity after the light guide plate is used is not sufficient for measurement.

Disclosure of Invention

The invention aims to provide a uniform light source generating device which has simple structure, is convenient for homogenizing a point light source and has high brightness and is used for a short-wave infrared imaging spectrum system.

In order to achieve the purpose, the uniform light source generating device for the short-wave infrared imaging spectrum system is characterized in that the incident end of an optical fiber bundle set formed by an optical fiber bundle set is restrained and fixed by a front end restraint device, a halogen tungsten lamp light source is close to and irradiates the incident end of the optical fiber bundle set, the light emitting end of each optical fiber bundle in the optical fiber bundle set is fixedly restrained by a rear end restraint device, the position and the area of the same optical fiber bundle at the incident end are different from the position and the area of the same optical fiber bundle at the light emitting end, and the light emitting end of the optical fiber bundle set is provided with a linear Fresnel lens.

In the scheme, firstly, the halogen tungsten lamp light source is irradiated to the optical fiber bundle set, the same number of point light sources can be obtained at the light outlet end of the optical fiber bundle set according to the specific number of the optical fiber bundle set, the primary homogenization of the light sources is realized, and in addition, the light sources are further homogenized according to the difference of the areas and the positions of the same optical fiber bundle at the light outlet end and the light inlet end, so that a uniform light source with uniform illumination and meeting the requirements on brightness is provided for the linear Fresnel lens, and a stable, reliable and uniform light source is provided for the next detection.

Drawings

FIG. 1 is a schematic structural view of the present invention;

fig. 2 is a perspective view of the rear end restraint of the present invention.

Detailed Description

As shown in fig. 1 and 2, in the uniform strip light source generating device for a short-wave infrared imaging spectroscopy system, an incident end of an optical fiber bundle set 20 formed by an optical fiber bundle set is constrained and fixed by a front end constraining device 30, a tungsten halogen lamp light source 10 is irradiated on the incident end of the optical fiber bundle set 20 in a close manner, a light emitting end of each optical fiber bundle in the optical fiber bundle set 20 is fixedly constrained by a rear end constraining device 40, the position and the area of the incident end of the same optical fiber bundle are different from the position and the area of the light emitting end of the same optical fiber bundle, and a linear fresnel lens 50 is arranged at the light emitting end of the optical fiber bundle set 20.

The optical fiber bundle set 20 in the above scheme is formed by a set of a proper number of single optical fiber bundles, and the specific number is determined according to the irradiated range. The light-emitting end of the optical fiber bundle set 20 enables the light sources to converge in the corresponding area directions by arranging the linear Fresnel lens 50, the light intensity of the light sources in the generated bright irradiation area can be increased under the condition that the light source of the halogen tungsten lamp is not changed, the utilization efficiency of the light sources is improved, and the light spot profile and the intensity of the uniform irradiation area can be flexibly adjusted by adjusting the distance between the linear Fresnel lens 50 and the light-emitting end of the optical fiber bundle set 20. The halogen tungsten lamp light source 10 can provide light waves with the wavelength range of 900-1700 nm, and the emitted light waves are approximately emitted into the optical fiber in parallel, so that the light waves can meet the requirement of the incident angle of the optical fiber.

The core of the present invention is that the position and area of the input end of the same optical fiber bundle 21 is different from the position and area of the output end thereof, that is, the position and area of the input end of a certain optical fiber bundle 21 in the optical fiber bundle set 20 may be changed at the output end, and when the input end is at the edge position, the optical fiber bundle set should be reasonably positioned at the middle part at the output end, or at least the area and position of the adjacent optical fiber bundle 21 around the optical fiber bundle set, that is, the relationship between the adjacent optical fibers 21 of each optical fiber bundle 21 at the input end and the output end should be changed, so as to make the illumination in the bright area presented by the optical fiber bundle set 20 formed by each optical fiber bundle 21 uniform.

The preferred scheme is that each optical fiber bundle 21 in the optical fiber bundle set 20 is in a re-uniform mixed state at the position and area of the light-emitting end compared with the position and area of the light-incident end. That is, the optical fiber bundle 21 originally located in the middle of the incident end is dispersed to the edge at the light-emitting end, the optical fiber bundle 21 originally located at the edge of the incident end is divided into the middle region of the light-emitting end, and the incident end is divided at the light-emitting end which is originally closely arranged, so that the optimal light source homogenizing effect can be realized.

If the test sample is transported by a conveyor belt into the imaging spectroscopy system for scanning testing, the source shape of the imaging spectroscopy system is optimized for the ribbon shape, and the corresponding back-end constraint 40 constrains the fiber optic bundle set 20 to a ribbon-like region. Therefore, the light source in the strip-shaped area is required to be just distributed over the width of the whole conveyor belt in the length direction, and the width of the light source is only about 10mm, so that the intensity of the generated light source can be enhanced, and the light source is utilized most effectively.

Specifically, the rear restraint 40 is a square block, through holes 41 penetrating through the block are uniformly distributed on the rear restraint, and each optical fiber bundle is inserted into and fixed in the through hole 41.

The light guide fiber bundles forming the point light sources are arranged in a uniform crossing mode, and the uniformity of the light sources is further improved.

The light source 10 of the halogen tungsten lamp is covered with a reflecting lampshade 11, and the reflected light provided by the reflecting lampshade 11 irradiates the incident end of the optical fiber bundle set 20 at a parallel light speed.

The reflector 11 and the front restraint 30 are disposed on the front frame 60, the rear restraint 40 is connected to the frame plate 42, and the frame plate 42 is further connected to the linear fresnel lens 50. This ensures stability of the relative positions between the elements.

The side of the section of the bracket plate 42 is provided with a trunnion or a pin hole 421 which is hinged with the rear bracket 70 and is matched with a locking unit, so that the deflection angle of the clamping structure can be manually adjusted and locked at a proper position according to the requirement of the light position.

In the present invention, the optical fiber material is a commonly used optical fiber, and the wavelength range of the optical wave suitable for the optical fiber material is relatively consistent with the wavelength range of the optical fiber material in the present invention.

The solution of the present invention that the light source 10 of the tungsten halogen lamp is matched with the fiber bundle set 20 is to divide the light source 10 of the tungsten halogen lamp with a larger size into tens of point light sources through the fiber bundle 21, so as to solve the problem that no point light source is available in the wavelength range of the present invention.

Claims

1. A uniform light source generating device for short-wave infrared imaging spectroscopy system, characterized in that: the incident end of the optical fiber bundle set (20) formed by the optical fiber bundle bundle is constrained and fixed by the front end restraint (30), and the halogen tungsten lamp The light source (10) is adjacent to the incident end of the optical fiber bundle set (20), and the light exit ends of each optical fiber bundle in the optical fiber bundle set (20) are fixed and restrained by the rear restraint device (40). The position and area of the incident end are different from the position and area of the light exit end, and a linear Fresnel lens (50) is arranged at the light exit end of the optical fiber bundle set (20).

2 . The light source generating device according to claim 1 , wherein the position and area of each optical fiber bundle in the optical fiber bundle set (20) at the light exit end are compared with the position and area at the incident end. 3 . Re-mixed state.

3. The light source generating device according to claim 1 or 2, characterized in that: the rear end restraint (30) restrains the optical fiber bundle set (20) into a strip-shaped area.

4 . The light source generating device according to claim 3 , wherein the rear end restraint ( 40 ) is in the shape of a square block, and through holes ( 41 ) passing through the block are uniformly distributed on the rear end restrainer ( 40 ). The optical fiber bundle is inserted and fixed in the through hole (41).

5. The light source generating device according to claim 1, wherein the tungsten halogen light source (10) is covered with a reflective lampshade (11), and the reflected light provided by the reflective lampshade (11) is irradiated at a parallel speed of light to the incident end of the fiber optic bundle set (20).

6. The light source generating device according to claim 1, 4 or 5, characterized in that: the reflector (11) and the front end restraint (30) are arranged on the front bracket (60), and the rear end restraint (40) is connected to On the support plate (42), a linear Fresnel lens (50) is also connected to the support plate (42).

7 . The light source generating device according to claim 6 , wherein a trunnion or pin hole ( 421 ) is hingedly connected to the rear bracket ( 70 ) on the side of the segment side of the bracket plate ( 42 ), and a locking unit is arranged in cooperation with the rear bracket ( 70 ). 8 . .