With modern lithographic technology, a compact spectrometer is designed to include a blazed micro-grating with cylindrical concave grating profile. In order to restrict the sagittal beam divergence and to reduce the size of the spectrometer, the micro-grating is embedded inside a pair of planar mirrors used as a slab waveguide. In the simulations for the effect of the waveguide, we discover that the focal pattern distortion introduced by the waveguide causes a blunted and side-tailed peak in the spectrum. The distortion can be managed by allowing some gap between the edge of the waveguide and the image sensor. Such a configuration has greatly improved the resolving power of the micro-grating in this compact system.
Regarding to researches on manufacturing process, the fabrication of nano structures on SWS (subwavelength structured)
grating are mainly produced by photo lithography. We find that UV light transmission efficiency of PET film
significantly drops 50% when we put nano structures on the surface of material. In this paper, we add nano structures
on the surface of PET film and create a UV band filter. Decent optical filtering effects can be achieved by combining the
characteristics of PET materials with nano structures on their surfaces.
In this article we will introduce a Light Emitting Diode (LED) lighting diffuser plate which diffuses light by
optical microstructure. In LED lighting, LED array is the most popular method to attain the illuminance requirement,
but this method will produce the glaring and non-uniform illuminance problems. Traditionally, diffuser, which is
comprised of diffuser particles, is used to solve the above problems, but it also produces another problem which is low
lighting efficiency. Therefore, we use optical microstructure to replace the diffuser particles to solve the problems of
LED lighting but only reduce a little lighting efficiency. Moreover, we could control the lighting area of the LED lamp
by designing the optical microstructure.
In this Letter, the identification device disclosed in the present invention is comprised of: a carrier
and a plurality of pseudo-pixels; wherein each of the plural pseudo-pixels is formed on the carrier
and is further comprised of at least a light grating composed of a plurality of light grids. In a
preferred aspect, each of the plural light grids is formed on the carrier while spacing from each
other by an interval ranged between 50nm and 900nm. As the aforesaid identification device can
present specific colors and patterns while it is being viewed by naked eye with respect to a
specific viewing angle, the identification device is preferred for security and anti-counterfeit
applications since the specific colors and patterns will become invisible when it is viewed while
deviating from the specific viewing angle.
Illumination system is an important component of projection display system, and decides the brightness and uniformity of the whole system. This paper will present a description of a simplification design and discuss the performance of LED illuminators with respect to light output, uniformity, and color performance.
Design a Fresnel lens for a concentrator to collect more sunlight onto the solar cell due to the efficiency and cost. Since 1970, the non-imaging concentrator was used for solar energy; most of them were reflecting mirrors. The non-imaging optical system provides large aperture and forgiving imaging requirements. The Fresnel lens used in non-imaging optical system was usually called non-imaging Fresnel lens. In this research, the Fresnel lenses were refracting optical elements but diffracting ones. According to the method of Ralf Leutz and Akio Suzuki , using minimum deviation and minimum dispersion to design a non-imaging Fresnel lens, which obeys the edge ray principle. Use optical software TracePro to simulate the non-imaging Fresnel lens, and each pitch size was 0.3mm and 200mm focus distant. Discusses the losses of non-imaging Fresnel lens and find out the relation of efficiency and F-Number. The optical concentration ratio could reach 15X (2-D) and 230X (3-D).
The design purpose of general lighting apparatus is how to induce the illuminating direction of light source efficiently and provide people comfortable vision. The lighting device has a reflective area. However, the reflective light was often caused a glare and a light pollution. It causes eyes discomfort and eyestrain. This problem has been overcome by the novel device in this study. This paper proposes a novel LED light apparatus with innovative reflector type, designed to reduce the glare for light comfort. The apparatus is consist of a reflective wall with many circumferential micro-structured and a circumferential light source as plurality of LED. In addition, a Fresnel type reflector can replace the traditional convex reflector. Multiple LED light sources will be guided to the reflective wall and Fresnel type reflector with in device, so ray of light will be well spreaded and sufficiently directed to or focused on the desired area. The micro-structured reflection type will enhances the light illumination efficiency by applying appropriate design of micro-structured reflecting layer.
This module combined the techniques of MEMS, near-field optics, fly head, and multiple beam. It organized the optical component and waveguide into a substrate. It integrated the multiple beam optical module for near-field high density recording, used the optics characteristic of the diffractive optical element, (DOE), generate multiple beams equally on the module, and reduce the spot size by using the near field optics. Simultaneously, quite a bit of information is recorded on the tracks of high density optical discs.