Abstract
A holographic optical element (HOE) was developed to collimate a monochromatic light-emitting diode (LED). The fabrication was achieved by the interference of collimated and diverging beams from a 532 nm laser to produce the required photonic structure in a self-developing photopolymer material. The experimental values of diffraction efficiency and spatial period across the HOE were compared with their expected theoretical values. Good agreement was found for the spatial period; however, the diffraction efficiency varied significantly across the lens. In this paper, two approaches have been taken to address this variation: (1) modification of recording geometry and (2) optimization of recording intensity and exposure time at constant energy. The performance of an optimized HOE (cylindrical holographic lens) was then demonstrated using a 532 nm laser beam. The optimized conditions for the cylindrical holographic lens were used to fabricate a spherical holographic lens of the same numerical aperture for LED applications. This type of lens has the potential to be used in combination with LED sources.
© 2018 Optical Society of America
Full Article | PDF ArticleMore Like This
Mei-Lan Piao, Ki-Chul Kwon, Hoon-Jong Kang, Kwon-Yeon Lee, and Nam Kim
Appl. Opt. 54(16) 5252-5259 (2015)
Hoda Akbari, Izabela Naydenova, and Suzanne Martin
Appl. Opt. 53(7) 1343-1353 (2014)
Julia Marín-Sáez, Jesús Atencia, Daniel Chemisana, and María-Victoria Collados
Opt. Express 26(10) A398-A412 (2018)