Abstract
We designed and fabricated two types of binary diffractive lenses using Electron beam lithography (EBL) on optical films film for controlling LED light. In the case of the binary diffractive convex lens with 2-mm focal length, it is possible to control the luminous intensity distribution. To improve the diffraction efficiency and realize a thin LED light source, the binary diffractive lenses with 100-μm-order focal length are effective. Furthermore we fabricated and characterized the binary diffractive concave lenses for application in LED lighting. It is found that white-light LEDs are strongly diffused by using the binary diffractive concave lenses.
Highlights
Light-emitting diodes (LEDs) are used increasingly as lighting devices because their efficiency has recently been improved
The binary diffractive convex lens with 2-mm focal length was fabricated on the PET film
The fabricated lens was mounted on the LED chip and spectral irradiance in the vertical direction was measured; Figure 3 shows the distribution of the irradiance
Summary
Light-emitting diodes (LEDs) are used increasingly as lighting devices because their efficiency has recently been improved. For such application, it is desirable to miniaturize LEDs for smaller lighting devices and control their luminosity. Conventional oval-lamp type LEDs cannot meet these requirements because their lens is approximately 5 mm in size and their light distribution is determined by the lens shape. To use LEDs as lighting devices, their luminosity distribution must be controlled because the LED itself is a point source. By using shortfocal-length (~100 μm) lenses, the spatial distribution of LED light can be controlled and a thin LED light source can be produced. Two types of lenses can focus light: an optical lens that uses refraction and a diffractive lens that uses diffraction. Diffractive lenses can be used as UV optical elements or thin optical elements [1]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
