Linear illumination device

Abstract

The invention discloses a linear illumination device which is arranged on a detection region and is used for providing an illumination light source required when an image sensor shoots an image from an image detection region. The device comprises a plurality of linear light sources, a light diffusion piece and a supplementary lighting device, wherein the plurality of linear light sources are distributed above the detection region in a circular arc shape by taking the detection region as a center, so that light rays can be projects towards the detection region simultaneously; the light diffusion piece is arranged between the detection region and the plurality of linear light sources, is used for projecting the light rays which are projected from the equal line-type light sources and are uniformly diffused onto the detection region, so that the reflected lights generated due to the irregular surface of an object to be detected are reduced, and the accuracy of the detected result is improved; and additionally, the supplementary lighting device is additionally arranged, a coaxial light in a direction same as the detection direction of the image sensor can be provided by the supplementary lighting device, and light sources from the image sensor can be increased.

Description

technical field [0001] The invention is a line lighting device, especially applied to a detection device, to provide a uniform light source for a detection area, so as to reduce the irregular reflected light caused by the irregular surface of the object to be measured, and increase the reliability of the detection result. Accuracy. Background technique [0002] Known lighting devices used in testing equipment usually use light sources to directly illuminate the detection area. However, this method may not be able to achieve uniform light illumination. For example, if it is used to detect objects with irregular surfaces (such as a laser label or the back of an optical disc, etc.), it will cause irregular and unstable reflected light, which will affect the imaging quality of the image sensor, resulting in a decrease in detection yield and / or an increase in false detection rate. [0003] In order to improve the above-mentioned lack of lighting, there are other known technologi...

AI Technical Summary

Problems solved by technology

[0002] Known lighting devices used in testing equipment usually use light sources to directly illuminate the detection area. However, this method may not be able to achieve uniform light illumination. For example, if it is used to detect objects with irregular surfaces (such as laser labels or the back of optical discs, etc.), it will cause irregular and unstable reflected light, which will affect the imaging quality of the image sensor, resulting in a decrease in detection yield and / or an increase in false detection rate

[0003] In order to improve the above-mentioned lack of lighting, there are other known technologies that can produce uniform linear lighting sources, such as figure 1 As shown, it mainly arranges the light source 11 on both sides of the base 12 of the detection area, and at the same time uses a reflector 13 for optical diffusion (as shown by the dotted line in the figure), so as to achieve a uniform line pattern on the detection area 14. The purpose of the light source, however, this technology still has the disadvantage of not being uniform enough to illuminate the light source. The reason is that although the detection area can obtain light sources from different directions and angles, the paths of light rays entering the detection area from different directions and angles are not equal, so that Due to the different degrees of attenuation of the light, it will cause irregular reflected light when detecting objects with irregular structures (such as objects with laser structures), resulting in poor imaging quality of the image sensor 15. Good, resulting in a decrease in detection accuracy

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