Detection system for spectral resolution of Rowland grating spectrometer

[0045] Example

[0046] Take the radius of curvature R750mm; grating diameter Φ63.5mm; spectral order -1; reticle density 2400g/mm; incident angle 40°; entry arm 574.5mm; 10um slit to be measured Roland grating spectrometer as an example, combined figure 1 This embodiment will be described.

[0047] First use the laser to adjust the grating state to the test state, that is, the spectrum of each order is on the same horizontal plane, and the image of the emitted spectrum is parallel to the grating line direction, and the Roland system to be tested is adjusted according to the design parameters by adjusting the incident cantilever to adjust the incident narrow The front and back positions and incident angles of the slits are connected to a line spectrum light source such as a mercury lamp. From the incident angle of the Roland grating, the incident arm length, the grating line, the radius of curvature and other parameters, the connected line spectrum light source is calculated by the grating equation to be relatively similar The exit angle and position of the two spectra, and adjust the detector to this position, such as the theoretical value of 312.5674-313.1844nm. Fine-tune the length and angle of the outgoing cantilever, so that the received spectral energy is the strongest and the waveform is symmetrical. Choose an integration time of 150ms to get the shot Figure 5 The spectrum line shown, Figure 5 It is expressed as 312.5674(right)-313.1844nm(left) under the 10um slit, and further measured 312.5674(right)-313.1844nm(left) under the 10um slit, please refer to Image 6.

[0048] Figure 7 For the measured 313.1844nm spectrum, by Figure 7 It can be seen that at this time, the half-height width of the spectrum line is 2.35 pixels; Picture 8 For the measured 313.1555nm spectrum, by Picture 8 It can be seen that at this time, the half-height and width of the spectrum line is 2 pixels; Picture 9 For the measured 312.5674nm spectrum, by Picture 9 It can be seen that the FWHM of the spectral line is 2.75 pixels at this time; Picture 8 , Picture 9 It can be seen that the linear dispersion rate is 1.7684 mm/nm. By calculating the interval of the received spectrum, the spectral resolution of the measured Roland grating spectrometer system can be obtained. At 313.1844nm, the measured spectral resolution of the Roland grating spectrometer system is 0.011nm; at 313.1555nm, the measured spectral resolution of the Roland grating spectrometer system is 0.009nm; at 312.5674nm, the measured Roland grating The spectral resolution of the spectrometer system is 0.012nm.