Evaluation of a Hadamard-coded photodiode-array spectrometer under low illumination

Area of Science:

• Spectroscopy
• Optical Engineering
• Instrument Design

Background:

• Hadamard spectrometers are recognized for multiplexing and throughput benefits.
• Conventional designs often necessitate moving entrance or exit masks.
• This limits practical applications and introduces mechanical complexity.

Purpose of the Study:

• To evaluate a breadboard photodiode-array Hadamard transform spectrometer.
• To compare a stationary, multislit entrance mask configuration against a single entrance slit.
• To assess performance, particularly signal-to-noise ratio (SNR) under varying illumination.

Main Methods:

• Experimental evaluation of two Hadamard spectrometer configurations.
• One instrument featured a stationary multislit entrance mask.
• The other used a traditional single entrance slit.

Main Results:

• The multislit, no-moving-parts instrument demonstrated higher throughput.
• This resulted in a superior signal-to-noise ratio in low-illumination conditions.
• Noise sources were analyzed for both configurations.

Conclusions:

• Stationary multislit Hadamard spectrometers offer significant advantages over single-slit designs.
• The improved throughput directly translates to better SNR in low light.
• Future designs can benefit from these findings to further enhance performance and reduce mechanical complexity.