Fig. 4.

Resolution test. a Measurements of the emission spectra of two HeNe lasers at 594 and 633 nm, respectively. The reconstructed spectra (circles) match well with the reference spectra (red solid line). The average measured linewidth is around 1 nm. b The PC spectrometer is used to measure the spectra of narrow-band light generated by the monochromator at 581, 582, 583, and 584 nm, respectively. The circles are results from the PC spectrometer. The red solid line is the ground-truth reference based on specification of the monochromator. c Comparison of 201 measured peak positions (from 550 to 750 nm, with 1 nm separation) with their ground-truth. d Comparison of the measured linewidths with the specification of monochromator