A compact, static, polarization-type Fourier spectrometer

Evaluation of an integrated Fourier-transform spectrometer utilizing a lateral effect position sensitive detector with a multi-channel Fabry–Perot interferometer

“…During the evaluation of the FT spectrometer it was shown that the leakage current affects the nonlinearity according to (10). Typical high precision PSDs have a nonlinearity of approximately ±0.1% over 80% of the active area, which in this case is about ±40 µm for the PSDs used.…”

“…An additional effect of leakage current as well as that of contact resistance is that the scaling of the PSD will change so that the range of the calculated position is reduced from ±1 × L/2 at the contacts to a lower value. The described model illustrates that the effect of leakage current on the calculated position can be reduced by a deduction from the denominator in (10). The intensity dependence and resulting nonlinearity cause a distortion of the reconstructed spectra as shown in figure 5 where additional parasitic components can Figure 5.…”

“…I d will act as a virtual light source situated in the middle of the active area if the leakage current is uniform across the p-n junction. Therefore the calculated position will be a linear superposition of these sources, as illustrated in (10). As shown in figure 1 the intensity of the incident light that passes through the slit and interferometer will be proportional to the intensity of the interference pattern and will depend on the position of the slit.…”

“…As shown in figure 1 the intensity of the incident light that passes through the slit and interferometer will be proportional to the intensity of the interference pattern and will depend on the position of the slit. Figure 4 shows the simulated position nonlinearity as introduced by I d according to the model in (10). The dotted sinusoidal line shows the simulated varying light intensity incident on the slit and PSD.…”

“…The incoming unpolarized light is separated at the output into two polarized light beams with the exit angle determined by the wedge angle of the prism. The beams then form an interferogram which is recorded by a single scanning detector or array [7][8][9][10]. This design does not require any imaging optics but does contain a number of elements such as Wollaston prisms and polarizing filters.…”