Close object imaging apparatus

Abstract

An apparatus for imaging an object at close range, comprising a light filtering layer (7) used for filtering from light rays scattered by the object the light rays having an angle of incidence that is greater than a filtration angle, a Fresnel lens (8) used for focusing the light rays having an angle of incidence that is less than the filtration angle, a wedge-shaped light guide (10) used for folding the light rays focused, and an image sensor (9) used for receiving at a focus the light rays focused and folded. The apparatus allows for implementation of close range imaging of the object, high definition imaging, and facilitated manufacturing and assembly, and is compact in size, light in weight, and easy to be moved and placed.

Description

technical field [0001] The invention belongs to the technical field of optical imaging, and in particular relates to a short-distance object imaging device. Background technique [0002] Traditional object imaging devices and methods are very simple, such as figure 1 As shown, the image sensor is set at a certain distance from the planar object, and the light emitted by the planar object is focused on the image sensor, thereby forming an image of the planar object through the image sensor. However, in order to obtain an image with uniform brightness and true proportions, according to the optical principle, the traditional imaging device for planar objects must place the image sensor far away from the planar object. Cause the whole device to be too bulky. [0003] The U.S. Patent No. US 7,660,047B1 discloses a short-range imaging device, such as figure 2 As shown, it places the left end surface of a transparent wedge-shaped flat plate in front of the lens of the image sen...

AI Technical Summary

Problems solved by technology

[0004] However, the short-distance imaging device must be designed to ensure that the facet angle on the right end surface of the wedge-shaped plate is consistent with the ideal design value, and a slight deviation will cause the converging point of the light on the left end surface to differ from the ideal converging point in design. A certain distance deviation will affect the definition of imaging; in the actual design and production process, a large number of tiny facets can be engraved on the small area of ​​the right end of the wedge-shaped plate. Distance imaging devices are less reliable and more expensive to manufacture

At the same time, the wedge-shaped flat plate is usually made of plexiglass, and its volume density is relatively high, so that the weight of the short-distance imaging device is relatively large, which limits the application of the short-distance imaging device in many occasions.

Images