Abstract

A CAOS line camera is introduced for spectral imaging of one-dimensional (1D) or line targets. The proposed spectral camera uses both a diffraction grating as well as a cylindrical lens optics system to provide line imaging along the line pixels’ direction of the image axis and Fourier transform operations in the orthogonal direction to provide optical spectrum analysis of the line pixels. The imager incorporates a coded access optical sensor (CAOS) structure based on a digital micromirror device (DMD). The design includes a line-by-line scan option to enable 2D spectral imaging. Line style spectral imaging using a 2850 K color temperature white light target illumination source along with visible band color bandpass filters and a moving mechanical pinhole is demonstrated for the first time, to the best of our knowledge, to simulate a line target with individual pixels in 1D that have unique spectral content. A ${\sim}{412}$ to ${\sim}{732}\;{\rm nm}$ input target spectrum is measured using a ${38} \times 52$ CAOS pixel spatial sampling grid providing a test image line of 38 pixels, with each pixel providing a designed spectral resolution of ${\sim}{6.2}\;{\rm nm}$. The spectral image is generated using the robust code division multiple access (CDMA) mode of the camera. Then, for what we believe is the first time, the high dynamic range (HDR) operation of the frequency division multiple access–time division multiple access (FDMA–TDMA) mode of the CAOS camera is demonstrated. The FDMA–TDMA mode also features HDR recovery like the frequency modulation TDMA (FM–TDMA) mode, although at a much faster imaging rate and a higher signal-to-noise ratio (SNR), as more than one CAOS pixel is extracted at a time. Experiments successfully demonstrate 66 dB HDR target recovery using both FDMA–TDMA and FM–TDMA modes, with the FDMA–TDMA mode operating at an encoding speed eight times faster than the FM–TDMA mode, given that eight FM channels are used for the FDMA–TDMA mode. The CAOS spectral imager can be used to image both full spectrum stationary line targets as well as spectrally map 2D targets using line scanning methods. The demonstrated FDMA–TDMA CAOS mode is suited for improved speed and SNR linear HDR imaging.

© 2021 Optical Society of America

Full Article  |  PDF Article
More Like This
Laser beam imaging via multiple mode operations of the extreme dynamic range CAOS camera

Nabeel A. Riza and Mohsin A. Mazhar
Appl. Opt. 57(22) E20-E31 (2018)

CAOS line camera

Mohsin A. Mazhar, Conor Russell, Mohammad Amiri, and Nabeel A. Riza
Appl. Opt. 58(33) 9154-9162 (2019)

Demonstration of 136 dB dynamic range capability for a simultaneous dual optical band CAOS camera

Nabeel A. Riza and J. Pablo La Torre
Opt. Express 24(26) 29427-29443 (2016)

References

You do not have subscription access to this journal. Citation lists with outbound citation links are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access OSA Member Subscription

Cited By

You do not have subscription access to this journal. Cited by links are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access OSA Member Subscription

Figures (12)

You do not have subscription access to this journal. Figure files are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access OSA Member Subscription

Tables (7)

You do not have subscription access to this journal. Article tables are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access OSA Member Subscription

Equations (10)

You do not have subscription access to this journal. Equations are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access OSA Member Subscription

Metrics

You do not have subscription access to this journal. Article level metrics are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access OSA Member Subscription