Portable lithium battery power supply. Use the touch color screen. The spectrum can be displayed directly. SD card storage. Fast scan 128-bit detector. Low cost and high precision spectrum tester.
Pr-650/pr650/pr655/pr655 spectral scanning photometer/photometer main uses:
Liquid crystal backlight test, photoelectric performance analysis of organic light-emitting diodes. Brightness, chromaticity, color temperature and spectrum test of various light sources. Measurement of reflection coefficient and transmittance.
Brief introduction of spectral radiometer
1, how do we study light?
Photometry is a science that measures the response of human eyes to light.
Because the human eye is a highly complex organ, this is undoubtedly a very difficult task. It involves psychology, physiology, physics and other disciplines.
1924, CIE (International Commission on Illumination) organized a meeting and defined the average response value of human eyes to light (the degree of strong response). Since then, photometry has become a modern subject. The Committee sampled and tested a large number of people and drew the obtained data into a bright curve. The curve shows that the human eye is most sensitive to green light, but weak to violet light and red light. PS: The so-called bright field of vision is an environment with strong light.
Experiments show that in the case of dark field of view, the human eye has completely different response values, in this case, the human eye can not distinguish colors. Then, a series of tests were carried out and the dark function of dark curve was drawn.
In order to characterize the properties of light more intuitively, we found that all visible light can be represented by red (R), green (G) and blue (B), and different proportions show different colors.
2. What is the spectral tristimulus value?
Do a color matching experiment by keeping the radiant energy value of each monochromatic light unchanged, and the obtained tristimulus value is called spectral tristimulus value, that is, the number of three primary colors matching the spectral color with equal energy. It is represented by symbols X, Y, z y, Z. Spectral tristimulus value is also called color matching function, and its value only depends on the visual characteristics of human eyes. The matching process is represented by an equation.
3. How do we measure light?
The main problem of photometric measurement is how to reproduce the response of human eyes to spectrum. The unique response characteristics of electron probe are completely different from those of CIE standard observer. Therefore, the probe must be able to correct the data according to the spectrum.
Scanning method is to use monochromator or multichannel detector (670 is 256 array detector) to complete the test. This method is to test the light intensity of the light source wavelength by wavelength, and calculate (match and integrate) the measurement data according to the apparent visual function to get the measurement result.
4. The working principle of 4.PR670 spectral radiometer:
By aiming the observation light path at Objectiv, the light enters the lens (optics), then enters a concave holographic diffraction grating (diffraction grating) and is divided into monochromatic light, and then a complete visible light band between 380 and 780 nm is obtained by a linear diode photodetector. After the calibration of human eye matching response curve (as shown in the third item above) and a series of mathematical operations, the parameters related to luminosity and chromaticity are obtained.
PR-650/655 PR670 are basically the same.