Optical density testing system and optical density testing device

An optical density testing system includes a light source, a first light splitting device used to divide the light into at least two light paths, at least two second light splitting devices used for receiving the at least two paths of light from the first light splitting device, first light-passing holes provided corresponding to each of the at least two second light splitting devices, a first filter device detachably arranged at each of the first light-passing holes, a first diaphragm detachably installed on each of the first filter devices, and a light receiving device. The second light splitting device is used to transmit the light onto a product to be tested through the first filter device and the first diaphragm. The light receiving device is used to receive transmitted light formed after the light passes through the product to be tested.

FIELD

The subject matter herein generally relates to an optical density testing system and an optical density testing device using the optical density testing system.

BACKGROUND

An optical density of an object is calculated by measuring a light intensity of a light and a light intensity of the light after passing through the object. Generally, an optical density testing device uses a single light source and a single probe, which can only measure one point at a time on the object; and can only test white light within a range of 300-800 nm, which cannot accurately simulate the test light source. Furthermore, for test points of different sizes, diaphragms of different aperture sizes are required to be replaced manually, which is troublesome.

DETAILED DESCRIPTION

FIGS. 1-10show an embodiment of an optical density testing system100including a light source1, a first light splitting device2arranged on a light emission side of the light source1, at least two second light splitting devices3cooperating with the first light splitting device2, first light-passing holes4provided corresponding to each of the at least two second light splitting devices3, respectively, a first filter device5detachably arranged at each of the first light-passing holes4, a first diaphragm6detachably installed on each of the first filter devices5, a light receiving device7cooperating with the first diaphragm6, and a product200to be tested placed between the first light diaphragm6and the light receiving device7.

The light source1is used to emit a light a. The first light splitting device2is used to divide the light a into at least two light paths and transmit the at least two paths of the light a to the corresponding second light splitting device3. The second light splitting device3is used to irradiate the light a through the first light-passing hole4, the first filter device5, and the first diaphragm6onto the product200to be tested. The light receiving device7is used to receive transmitted light passing through the product200to be tested.

As shown inFIG. 2, a lens10is provided between the light source1and the first light splitting device2for focusing and transmitting the light a emitted by the light source1to the first light splitting device2.

The first light splitting device2includes at least two first beam splitting prisms combined together. Each second light splitting device3includes a second beam splitting prism. The first beam splitting prisms and the second beam splitting prisms can completely reflect the light a. In one embodiment, the first light splitting device2is composed of two depolarizing beam splitting prisms (NPBS), which divide the light a emitted by the light source1into the two paths and change a transmission direction of the two paths by 90°. Then, each of the two paths enters the corresponding second light splitting device3. Each of the second light splitting devices3is composed of a depolarizing beam splitting prism, and a transmission direction of each of the two paths is changed by 90° to enter through the corresponding first light-passing hole4. In actual use, a number of paths that the first light splitting device2can split the light a into can be designed according to actual needs, so that multiple points of the product200to be tested can be measured at the same time to improve a testing efficiency.

As shown inFIGS. 1, 3, and 9, the first light-passing holes4are provided on a test platform11, and a positioning device12is provided on the test platform11around each of the first light-passing holes4for detachably fixing the first filter devices5. In one embodiment, the positioning device12is a magnet, and the magnet is embedded in a surface of the test platform11so that the magnet is flush with the surface of the test platform11and will not impact the product200to be tested. Two surfaces of the first filter device5and two surfaces of the first diaphragm6are also embedded with the positioning device12, so that the first filter device5and the first diaphragm6can be disassembled and assembled conveniently and quickly.

As shown inFIG. 6, the first filter device5includes a hollow fixed frame51, a filter52provided in a hollow position of the fixed frame51. The filter52can be matched with different first filter devices5to achieve the purpose of filtering different wavelengths of light to measure the light density at different wavelengths.

As shown inFIG. 5, the first diaphragm6includes a positioning disk61, a through hole62provided in a middle portion of the positioning disk61, and an aperture adjustment device63provided on a side wall of the through hole62. The aperture adjustment device63is used to adjust an aperture size of the through hole62.

In one embodiment, the aperture adjustment device63may adopt a mechanical shutter structure design. A groove (not shown) is provided in a middle of the positioning disk61. An opening direction of the groove faces the through hole62. The aperture adjustment device63is fixed in the groove. The aperture adjustment device63includes an adjusting device (not shown) fixed in the groove, a plurality of blades631arranged on the adjusting device, and an adjusting rod632arranged on a side of the adjusting device. The plurality of the blades631is located in the through hole62and can be combined to define a round hole in the middle. The adjusting rod632extends from the positioning disk61in a direction away from the through hole62and can move along a first direction substantially parallel to a surface of the positioning disk61. The adjusting rod632is engaged with the adjusting device through gears for opening and closing the blades631to achieve the purpose of adjusting the aperture of the through hole62, so that the same first diaphragm6can adjust the aperture size for different measurement points. Thus, there is no need to manually replace the first diaphragm6with another diaphragm of a different aperture size for different measurement points, which is convenient and does not require multiple diaphragms.

As shown inFIG. 3, in one embodiment, the through hole62is a circular through hole, a hollow portion of the fixing frame51is a circular through hole aligned with the through hole62, and the first light-passing hole4is also a circular through hole aligned with the through hole62and the hollow portion of the fixing frame51to facilitate light transmission. At the same time, rubber buffer layers are provided on upper and lower surfaces of the fixed frame51and the positioning disk61to buffer contact with the product200to be tested. The rubber buffer layers can also be replaced by other soft materials.

As shown inFIGS. 3, 4, 9, and 10, the light receiving device7includes a sleeve71, a light receiver72arranged in the sleeve71, and a light blocking layer73arranged in the sleeve71adjacent to the first diaphragm6. The light receiver72is embedded in the sleeve71a certain distance from an edge of the sleeve71to prevent external light from affecting light received from the product200to be tested. In one embodiment, the light blocking layer73is a black rubber buffer layer, which can prevent external light from entering the sleeve71and buffer contact with a surface of the product200to be tested. An outer ring of the sleeve71is also provided with the positioning device12. The positioning device12is a magnet embedded in the sleeve71and will not cause damage to the product200to be tested.

As shown inFIG. 1, in one embodiment, the light receiving device7further includes a transmission line74to establish a communication connection with a optical density testing device13. The transmission line74may be an optical fiber or other optical transmission material. The transmission line74can be freely bent, and a length of the transmission line74can be designed according to actual needs. A size of the product200to be tested may not be limited, and the optical density of large objects can be measured. At the same time, only one communication interface can be provided on the optical density testing device13, and multiple light receiving devices7can be connected to the optical density testing device13through an adapter.

As shown inFIGS. 1, 2, 4, 7, 8, and 10, when it is necessary to test the optical density of a large-sized product200, the optical density testing system100further includes an external light source8. The external light source8includes a light transmission device81coupled to an optical path of the light source1, a fixing device82provided at an end of the light transmission device81away from the light source1, a second light-passing hole83provided on the fixing device82, a second filter device84detachably provided at the second light-passing hole83, and a second diaphragm85detachably provided on the second filter device84. The light receiving device7can be arranged on a light exit side of the second diaphragm85. The light source1emits the light a through the second light-passing hole83, the second filter device84, and the second diaphragm85, and the light a enters the product200to be tested. Transmitted light formed by the light a passing through the product200to be tested is received by the light receiving device7. Thus, the external light source8can realize the optical density testing of a large-sized product200.

In one embodiment, the second filter device84and the first filter device5have a same structure, and the second diaphragm85and the first diaphragm6have a same structure.

In one embodiment, the light transmission device81includes a light receiving end811, a transmission optical fiber812, and a light output end813. The light receiving end811is configured to receive the light a of the light source1, and the light output end813is used to output the light a. The lens10is provided between the light receiving end811and the light source1for focusing the light a emitted by the light source1to the light receiving end811. In one embodiment, the transmission optical fiber812is a hose-clad optical fiber, and the light a from the light source1is focused in the transmission optical fiber812through the lens10. The light a is totally reflected and transmitted with low loss. The transmission optical fiber812can also be replaced by other light transmission materials. The light output end813includes a light outlet814. The light outlet814is designed with a certain oblique angle, and the light outlet814is chamfered to prevent damage to the light source1caused by the reflection of the optical fiber. In one embodiment, the fixing device82is a flange, and the light output end813is aligned with the second light-passing hole83on the flange, which is convenient for connection. The fixing device82, the second filter device84, and the second diaphragm85are all fixed together by a detachable connection device, such as an embedded magnet.

As shown inFIG. 1, the optical density testing device13is used to obtain a light intensity of the light a. The optical density testing device13includes the above-mentioned optical density testing system100. The optical density testing device13is also used to receive the transmitted light output by the light receiving device7and determine the light intensity of the transmitted light, and then according to the light intensity of the light a and the light intensity of the transmitted light, determine the optical density of the product200. The optical density testing device13also includes a display screen14and an adjustment button15. The display screen14and the adjustment button15are both communicatively coupled to the optical density testing device13. The display screen14is used to display a test result. The adjustment button15switches information displayed on the display screen14.

FIG. 11shows another embodiment of a first filter device9. The first filter device9includes a hollow fixed frame91, a step92provided on an inner side of the fixed frame91, an opening94provided on the step92, and a filter93detachably provided on the step92. The opening94is defined on a side wall of the step92and extends toward an outer edge of the fixed frame91. In one embodiment, by designing the filter93to be detachable, there is no need to design multiple fixing frames91, and only a different filter93needs to be replaced, which saves costs and facilitates storage. Specifically, the filter93can be pasted onto the step92to facilitate disassembly and assembly. At the same time, the design of the step92does not allow the filter93to protrude from the surface of the fixed frame91to damage the product200, and the opening94can facilitate disassembly and assembly of the filter93.

Compared with the related art, the optical density testing system100provided by the present disclosure has the following beneficial effects:

1. After the light emitted by the light source is focused by the lens, it can be divided into multiple paths through the first light splitting device, and then with the second light splitting device, the purpose of simultaneous testing of multiple points on the product to be tested can be achieved.

2. The detachable filter device can meet the measurement requirements of optical density at different wavelengths by changing different filter devices and improve accuracy.

3. The detachable diaphragm is easy to use, and the size of the aperture can be adjusted to adapt to the size of a point to be tested, thereby meeting the test requirements of different points to be tested.

4. By setting up an external light source, the external light source and the original light receiving device cooperate with each other, so that a large-sized product can be tested.

5. The light receiving device can be bent freely without space constraints, and can measure large objects to be tested.

6. The light transmission material adopts an optical fiber having stable light output and low loss.