Integrating sphere overview:>
1. The integrating sphere test is used to measure the light source and its accessories to better understand and control the light quality and performance of light sources. The integrating sphere is a miniature spherical light environment, whose inner wall surface is covered with a reflective coating with nearly ideal diffuse reflection properties. Any position in the sphere is uniformly irradiated to generate a irradiance value, which can be used as a reference standard. The integrating sphere helps the light source release internal light quality energy with a large amount of reflected light and diffuse reflected light, and characterizes its photoelectric performance. In general, the reflectance is obtained by using the reflected light and diffuse reflected light of a standard reflector (a reflective surface with known reflectance) irradiated into the integrating sphere to avoid contaminating the surface of the sample; usually, the sample and standard can be measured The ratio of reflectance between reflectors is the reflectance of the sample. LED Photometric Integrating Sphere> system can also be used to measure luminous flux, light intensity, relative color temperature, color rendering index, and even other photoelectric parameters such as the attenuation rate of light in a specific wavelength range.
2. LED photometric integration The ball tester is an authoritative and effective device, which can effectively detect the chromaticity parameters such as color temperature, luminous flux, and internal temperature of the light source. It uses integrating spheres, related instrument measurement systems, and software systems to accurately measure and reflect the lighting conditions of the light source under changes in light sources. It is widely used in quality inspection and review, proofreading, and development and verification of mechanical equipment. And the determination of the light energy performance of electronic equipment and circuits.
Applications of the integrating sphere:>
1. The light receiver is a device that detects changes in illuminance. Control, automatic projection and other systems provide important parameters. The basic principle is to convert the change of illuminance inside and outside the small hole panel into the change of current. Sunlight enters the integrating sphere through a small hole, and then scatters on the inner wall to form a transient illuminance radiation to the inner wall. One or more light probes on the inner wall convert this change into electrical pulse signals and output them to intelligent control system.Therefore, the incident light intensity can be sampled within a certain period of time and the parameters of the intelligent control system can be adjusted to realize the detection of the external light intensity.
2. Using an integrating sphere can make an evenly illuminated object surface. The reason why it can be evenly illuminated is that some bulbs are installed on the inner wall of the integrating sphere. Sub-diffuse reflection, forming a uniform bright glowing sphere. The integrating sphere can be used to measure the vignetting coefficient of the photographic objective lens and the uniformity of the illumination of the image plane. Its field of view exceeds 2w>140 degrees, and the positions of the entrance pupil and the light exit hole basically coincide.
3. The research shows that the spherical collimator can be used to measure the stray light coefficient of the telescope. The device uses a spherical body as a collimator, and two holes are opened at both ends of the horizontal axis of the spherical body. One hole is installed with a collimating objective lens, and the other hole is installed with a hole plug and an extinction tube to form a black body, and then replaced with a white plug for Measures the stray light factor for the telephoto factor. The device measures the illuminance of the black body image and the Besser image through the photodetector, so as to obtain the stray light coefficient of the telescope. In this way, a fast and accurate stray light coefficient test can be realized, which provides a support for the development of optical instrument technology.
LED Photometric Integrating Sphere> is a special instrument for measuring illuminance, which has a hollow spherical structure whose inner wall is coated with diffuse reflection materials, and one or several openings, For light sources and measuring instruments for testing. The inner wall of the ball is generally coated with a material whose diffuse reflection coefficient is close to 1. The commonly used ones are magnesium oxide or barium sulfate. The ratio of the area of the ball at the small hole of the integrating sphere to the area of the entire inner wall of the ball should be as small as possible to obtain higher measurement accuracy. The spectral reflectance of the integrating sphere is more than 99% in the visible spectrum range, and it is reflected multiple times in the sphere to form a uniform illuminance, which is used to measure the illuminance.