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Hyperspectral imaging has numerous applications in a range of fields for target detection. While its original applications were in remote sensing, new uses include analyzing food quality, agriculture and medicine, Hyperspectral imaging has shown utility in fluorescence microscopy for detecting signatures from many fluorescent molecules, but acquisition speeds have been slow due to the need to acquire many spectral bands and the light losses associated with spectral filtering. Therefore, a novel confocal microscope, the 5- Dimensional Rapid Hyperspectral Imaging Platform (RHIP-5D) was designed and is undergoing testing to overcome acquisition speed and sensitivity limitations. The current design utilizes light-emitting diodes (LEDs) and a multifaceted mirror array to combine light sources into a liquid light guide. Initial tests demonstrated feasibility and we are now working on determining the ideal location of the liquid light guide, LEDs, lenses and mirror array to optimize optical transmission. A computational model was constructed using Monte Carlo optical ray tracing in TracePro software (Lambda Research Corp.). LED sources were simulated by importing irradiance properties from the manufacturers’ specifications. Optical properties of lenses were modeled using lens files available from the manufacturer. Analysis of the model includes geometry and parametric optimization, assessing lens power, mirror angles and location of optical elements. Initial results show an increase of transmission is possible by up to 20%. Future work will involve evaluating the position of the liquid light guide as well as analyzing lens configurations to further increase optical transmission.
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High-efficiency anti-reflective modification of freeform elements and cylindrical lenses for arrayed wide-field astronomical corrector units
Randomly distributed anti-reflective nanostructures were fabricated on both surfaces of cylindrical lenses and freeform optical elements using a plasma-assisted reactive-ion etching technique. An average spectral transmission of 98% was measured across the wavelength range from 340 to 800 nm. Mid-band full-angle directional scatter measurements show a difference of six orders of magnitude in transmission intensity between specular and off-specular angles. Measurements before and after the etching process show little to no wavefront distortion for the cylindrical lenses. The enhanced transmission optics were used as part of the dual-unit arrayed wide-field astronomical camera system tested on the Harlan J. Smith telescope at the McDonald Observatory, and their performance was contrasted with conventional thin film coated component performance.
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- Award ID(s):
- 2107947
- PAR ID:
- 10558397
- Publisher / Repository:
- SPIE JATIS
- Date Published:
- Journal Name:
- Journal of Astronomical Telescopes, Instruments, and Systems
- Volume:
- 10
- Issue:
- 02
- ISSN:
- 2329-4124
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1117/1.JATIS.10.2.025007
