Device and method for detecting size of micro object

Abstract

The invention discloses a micro object size detection device and a detection method. The detection device comprises a laser emitter used for emitting parallel light beams; a receiver provided with a photosensitive array and is used for receiving a diffraction image formed after the parallel light beams pass through the measured object; a clamp arranged between the laser transmitter and the receiver and is used for clamping the measured object; a distance adjusting mechanism respectively connected with the receiver and the clamp and is used for adjusting the distance between the photosensitive array and the measured object; and a control module electrically connected with the receiver and the distance adjusting mechanism and used for receiving the diffraction image received by the photosensitive array and controlling the distance adjusting mechanism, so that the diffraction fringe distance meets the requirement. According to the detection device, through omitting a lens in the prior art and adopting an automatic spacing adjustment mode, detected objects with different sizes can generate diffraction images with relatively high resolution, and the detection precision and the detection range are improved.

Description

technical field [0001] The invention relates to the field of sensors, in particular to a detection device and a detection method for the size of a tiny object. Background technique [0002] In the field of industrial precision detection, it is often necessary to detect the size of tiny objects such as thin metal wires and optical fiber cores. The traditional method of measuring size is to use a through-beam laser size measuring sensor. The key to this sensor is to establish a beam of parallel light after being collimated with a laser light source. The beam irradiates the photosensitive element. A proportional "shadow" will appear on the component, and the size of the object can be obtained by measuring the size of the shadow or the change in the amount of light received. The principle of this method is as Figure 9 shown. [0003] But for tiny objects, such as objects with a size of 0.1mm, the diffraction fringes caused by laser will seriously affect the judgment of the "s...

AI Technical Summary

Problems solved by technology

[0005] The disadvantage of current technology is that the size and resolution of the receiving array will limit the measurement range of tiny objects

From the formula d=λfv, it can be seen that since the wavelength λ and the focal length f have been fixed in the device, the measurable tiny size d is affected by the eigenfrequency v of the object. When the eigenfrequency v is too small, the space period is too large When , the receiving array may not be enough. Similarly, when the eigenfrequency v is too large so that the space period is too small, the receiving array cannot distinguish, resulting in measurement failure

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