Quick detection device and method for photometric characteristics of motor vehicle lamp

Abstract

The invention relates to the optical-mechanical-electrical technical field, and particularly relates to a quick detection device and method for the photometric characteristics of a motor vehicle lamp. The device comprises a darkroom and two industrial CCD (Charge Coupled Device) cameras, wherein the darkroom is arranged opposite to a lamp fixing seat, the horizontal center axes of the darkroom and the lamp fixing seat are on the optical axis of the lamp, and an imaging screen is installed in the darkroom via a screen moving mechanism; the two industrial CCD cameras are connected to the upper and lower parts of the darkroom; and the industrial CCD cameras, a driving motor of the screen moving mechanism and a driving motor of an electric turntable are electrically connected with an industrial control computer. The detection method comprises equipment preparation, lamp installation, image acquisition, image processing, sample calibration and database establishment, and lamp photometric characteristic test. According to the device and the method, images are shot by a CCD planar array device, the relation between the illumination of the lamp and the gray value of the shot images is acquired, a database is established by using data obtained by multiple experiments of the lamp calibrated according to the illumination, and then the digital quantity of each pixel is inversed to the illumination of each point by spatial sampling.

Description

technical field [0001] The invention relates to the field of motor vehicle detection, in particular to a device and method for quickly detecting light distribution performance of motor vehicle lamps. Background technique [0002] The light distribution performance of motor vehicle lights is a very important item in national mandatory standards such as GB4599-2007, GB5948-1998, GB17510-2008. The light distribution performance not only has the requirements of light shape, but also has strict requirements for each test point. Require. Its function is to illuminate the road conditions without affecting the eyes of the drivers of the vehicles coming from the opposite direction; meanwhile, it also serves as a reminder to other driving vehicles. [0003] The method of testing the light distribution performance of motor vehicle lights has a great influence on the testing results. According to different testing principles, many different testing techniques and methods have been prod...

AI Technical Summary

Problems solved by technology

The biggest disadvantage of the first three methods is that they can only measure a limited number of points, and cannot measure the entire light pattern of motor vehicle lights, which has almost no experimental application value; The test method, which is equipped with computer automatic control and data collection, can obtain relatively complete screen illuminance distribution data (the coverage of illuminance distribution data is related to the description interval angle)

However, this kind of system device is relatively complicated, there are many supporting equipment, and the cost is high. Moreover, this method has high requirements for the lamp inspection site and inspection personnel, and the detection efficiency is low.

The CCD device test method uses the CCD area array device to measure the entire illuminance distribution, and can also record the illuminance image, so as to compare and analyze the light distribution performance of various lamp types. This method is not only fast and accurate, but also There are problems such as the inhomogeneity and nonlinearity of the photoelectric response of each photosensitive element of the CCD device, and the distortion and noise in each link of the camera system.

[0004] CN201110231773.7 The self-adaptive detection method for the light distribution performance of motor vehicle headlights based on the camera method uses a single camera to take pictures and samples the lamp projection screen. There are blind spots in the camera sampling, that is, it is impossible to collect light samples from all areas of the car lights, and it is impossible to accurately judge the light distribution performance of the car lights. It is time-consuming and laborious to find the correct position, and the results are not accurate; (2) There is no sample calibration and no benchmark established. It only uses the digitization of the image to calculate the illuminance of each point, which has the disadvantages of large amount of calculation and long detection time.

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