Spectrum irradiance standard light source for ultraviolet optical instrument radiometric calibration

Abstract

The invention provides a spectra irradiance standard light source which is used for radiometric calibrations of ultraviolet optical instruments, which comprises a light source component, a lifting holdfast, a collimating component, and a lamp chamber, wherein the front end of the lamp chamber is provided with a window which is used for outputting xenon lamp radiations, a xenon lamp power supply is connected with a xenon lamp electrically, a port of a cylinder lens hood is communicated and installed concentrically with the window which is on the lamp chamber, a piece of lens and a diaphragm are arranged in turn on a xenon lamp radiation light path inside the lens hood, the xenon lamp is located on the focus of the lens, the diaphragm is located on the other side, the collimating component and the lamp chamber are installed commonly on the lifting holdfast, an extra-quiet xenon lamp which is selected by the invention has a short arc xenon lamp which has a comparatively strong radiation strength in an ultraviolet wave band, the invention also adopts a high durable cathode which enables that arc points of the xenon lamp has no drifts and fluctuations , the light source can be used for ultraviolet wave band200-2000nm, visible wave band, and near infrared wave band, in particular for the ultraviolet wave band with a wave length less than 400nm, and signal-to-noise ratios of calibrations can be increased effectively due to high irradiance.

Description

technical field [0001] The invention relates to a ground radiation calibration instrument for an earth observation remote sensing instrument, in particular to a spectral irradiance standard light source for radiation calibration of an ultraviolet optical instrument. Background technique [0002] In optical remote sensing, in order to accurately obtain the physical parameter information of the measured object, radiometric calibration of the instrument is an important aspect of optical remote sensing. Especially for on-board optical remote sensing instruments, in order to ensure the long-term stability and measurement accuracy of the instruments, the on-board optical remote sensing instruments are usually required to measure the solar irradiance to monitor the long-term changes of the instruments in the space environment. For this reason, in the development process of on-board optical remote sensing instruments, radiometric calibration of the instruments is an important aspect...

AI Technical Summary

Problems solved by technology

If the distance between the 1000W spectral irradiance standard tungsten halogen lamp and the instrument to be calibrated is shortened, the energy of the light source can be guaranteed; however, it not only introduces the influence of divergent light beams on the calibration accuracy of the instrument, but also increases the influence of stray light, making the Irradiance calibration accuracy is difficult to guarantee

The second is that the divergence angle of the calibration light source is much larger than the opening angle of sunlight, and the resulting stray light will bring additional measurement errors; the third is that the distance from the 1000W spectral irradiance standard halogen tungsten lamp to the instrument is difficult to accurately measure

[0005]The main defect of the radiance calibration of the instrument is that the 1000W spectral irradiance standard tungsten halogen lamp has low radiation intensity in the ultraviolet band, which reduces the The signal-to-noise ratio of band irradiance calibration; in addition, the distance measurement error between the 1000W spectral irradiance standard tungsten halogen lamp and the standard diffuse reflector is still an important source of measurement error

However, due to the large filament size of the 1000W spectral irradiance standard tungsten halogen lamp and the long focal length of the collimating mirror, it can only partially solve the above-mentioned stray light problem, and the problem of low radiation intensity in the ultraviolet band still exists

[0007] Although the short-arc xenon lamp has a strong radiation intensity in the ultraviolet band, it can effectively improve the signal-to-noise ratio of radiation calibration in the ultraviolet band, and is widely used in spectrometers as a light source in the ultraviolet, visible and near-infrared bands, but due to its arc The drift and fluctuation of the point are large, resulting in an unstable light source, so the short-arc xenon lamp cannot be used as a standard light source (see reference 2: HAMAMATSU SUPER-QUITE XENON LAMPS)

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