Using diffuse reflector calibration, the diffuse reflector is required to fill the entire aperture and field of view of the instrument. The reflective surface is close to the ideal Lange surface, providing near-saturated radiance with good uniformity. Due to the possibility of long-term exposure to the space environment, materials must withstand the test of the space environment. The goal of the next-generation GOES imager for visible light calibration is: absolute calibration error <5%, relative calibration error <1%. The visible channel of the imager must be on-board full-light path, full-caliber calibration, requiring calibration source The stability is less than 1%. To this end, the idea of ​​using the sun and the perforated plate for calibration is proposed. Due to the diffraction effect, the image formed by the sun through the small holes of the perforated plate can cover the scanning mirror with a larger area and more uniformity, and the appropriate pitch is selected. The channel with wider spectrum will not have interference effect, and the effect of the full aperture will be better. When the calibration is performed, the perforated plate is inserted into the scanning mirror, and after the calibration is completed, the perforated plate is withdrawn. Structure and operation are relatively simple. Built-in lights have been used for on-board calibration of remote sensing instruments. Although long-term calibration is increasingly favoring natural light source targets, built-in light sources have great advantages in monitoring short-term changes in system response, especially for incomplete Light path calibration.
In China, the CCD camera on the “Resource One†satellite uses a built-in lamp for calibration. The calibration part comprises a linear filament halogen lamp, a rotating filter disk and an illumination optical system. The light enters the photographic optical system through a small mirror in front of the illumination optics and a side-view mirror that is rotated about 45° above the optical axis, onto the CCD of the focal plane. Landsat (Landsat) load ETM also uses built-in lights for short-term calibration. The German MOS also uses a built-in lamp for relative calibration of the non-all-optical path. The built-in lamp calibration generally requires auxiliary optical devices, such as the Kola illumination system, the turning lens, etc., to ensure the uniformity of the light source in the field of view and the entrance pupil, and to introduce the light source into the optical system of the instrument. The internal scaler requires good stability of the light source and provides multiple levels of illumination as much as possible.
The upscale faux fox fur and Knitting Wool products reach the domestic and international high level. Products have been exported to the United States, Australia, Japan, Russia and Vietnam. In addition, according to the report from international accredited testing institutions, the test of formaldehyde in some products is ND level. The company receives high praise from the international specialists.
In the last century, the invention of faux fur advanced human civilization. Faux fur products, which look very similar to the real animal fur, could be produced and no harm to animals. Faux fur products are not only warm, easy care and diverse, but also greatly contribute to protecting animals and ecology for human beings.
At the same time in the last century, a company, specialized in faux fur research and development, was founded on the coast of the beautiful Tai Lake --- Wuxi Shuangda Plush Co., Ltd.
Jacquard Printing Plush,Animal Print Fleece,Printed Micro Velvet Fabric,Plush Curtain Fabric
Wuxi ShuangDa Plush Co., Ltd. , https://www.sd-fauxfur.com