Working principle of caliper

        There are two commonly used non-contact measurement methods in China, one is based on CCD devices receiving light signals, and the other is laser scanning measurement. Let's take a look at their basic working principles.
The first measurement principle: CCD size measurement
Schematic diagram of CCD caliper principle:

    CCD size measurement systems are basically composed of CCD image sensors, optical systems, data acquisition and processing systems. Let's first take a look at the basic principle of using CCD measurement: the basic principle of non-contact measurement using linear CCD parallel light method: placing the linear CCD in the parallel light path, the object being measured in front of the CCD in the light path will be partially blocked by the object, so there will be a shadow at the CCD receiving end. The width of the shadow has a one-to-one correspondence with the size of the object, and we calculate the size of the measured object through circuit and software processing.
Second measurement principle: laser scanning measurement
Schematic diagram of laser scanning principle:

    Laser scanning diameter measurement uses the beam emitted by the laser to pass through a polyhedral scanning mirror and a scanning optical system, forming a continuous high-speed scanning beam parallel to the optical axis. The workpiece placed in the measurement area is scanned at high speed and received by a photoelectric receiver placed opposite the workpiece. The light projected onto the photoelectric receiver is intercepted when the beam scans the workpiece. Therefore, by analyzing the signal output by the photoelectric receiver, data related to the diameter of the workpiece can be obtained.