A spectroscopic measuring device

Abstract

The invention discloses a spectral measurement device, comprising optical elements including an incidence slit, a dispersing element and an imaging element. A spectral selection thin film is plated on the surface of each optical element; the selection wave band of the spectral selection thin film corresponds to a measurement wave band of the spectral measurement device; the optical elements plated with the spectral selection thin film only can emit light within the selection wave band of the spectral selection thin film so as to greatly weaken light with other wavelengths in a light path, Thus the stray light level of an optical system is greatly reduced.

Description

technical field [0001] The invention belongs to the field of optical radiation measurement, and in particular relates to a spectrum measurement device. Background technique [0002] The spectral measurement device is an optical instrument used to measure the spectral power distribution of illuminants, and is widely used in light source radiation measurement, color measurement, element identification, chemical analysis and other fields. Spectrum measurement devices include various types, which are divided into vacuum ultraviolet / ultraviolet / visible light / near-infrared / infrared / far-infrared spectrometers according to the spectral range they can work normally; Interference spectrometer, etc.; according to different detection methods, it is divided into spectrometer, spectrograph and photoelectric spectrometer, etc.; according to the function and structural characteristics of the device, it is divided into monochromator (grating / prism / double monochromator, etc.) and multi- Colo...

AI Technical Summary

Problems solved by technology

[0004] In traditional spectral measurement devices, aluminum-coated concave mirrors are commonly used imaging components, but aluminum-coated concave mirrors can reflect ultraviolet-visible-infrared light radiation with high reflectivity, such as figure 1 As shown, this broadband reflection characteristic will bring considerable stray light to the spectroscopic measurement device

Taking a typical Czerny-Turner mechanical scanning monochromator as an example, the dispersed light is incident on the converging mirror (aluminized concave mirror), and the scanning mechanism drives the converging mirror to rotate, thereby reflecting different monochromatic light to the exit slit , to realize the scanning of the entire spectrum, due to the overlap of different diffraction order spectra, at the same position of the converging mirror, there may be different diffraction order spectra of the monochromatic light to be measured and other wavelengths at the same time, and the aluminum-coated mirror reflects non-selectively All the light at this position causes a large amount of stray light of other wavelengths to be mixed in besides the monochromatic light to be measured at the exit slit

In addition, for a polychromator using an array detector, light of different wavelengths is received and detected by different pixel areas of the array detector. Since the measurement light and non-measurement light of different wavelengths are reflected by the aluminum-coated concave mirror to the same pixel area, Causes a large amount of stray light from other non-measurement wavelengths to be mixed into the pixel area

Therefore, for a spectral measurement device that uses an aluminum-coated mirror as an imaging element, its non-selective broadband spectral reflection characteristics will bring a large amount of stray light to the measurement device, resulting in large measurement errors

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