&lt;title&gt;Light collection efficiency for light valve projection systems&lt;/title&gt;

Brennesholtz, Matthew S.

doi:10.1117/12.237020

Cited by 31 publications

(23 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…To develop an LV-based projector, the optical efficiencies of all the elements from the light source to the screen must first be determined; and its design should achieve overall matching of these elements. [15][16][17] In this paper, it is assumed that the optical transmission and reflection factors, which results from losses introduced by all of the optical components in the projector, are negligible. The light source used for the projector may be a xenon lamp or a metal halide lamp with a short arc gap, for example, and the total luminous flux ⌽ S output from such a diffused light source is given as…”

Section: Projector Efficiency and Schlieren Opticsmentioning

confidence: 99%

Design and fabrication of a projection display using optically addressed polymer-dispersed liquid crystal light valves

et al. 2000

View full text Add to dashboard Cite

A prototype projection display consisting of optically addressed polymer-dispersed liquid crystal (PDLC) light valves and a Schlieren optics is designed, built, and evaluated. This projection display, which controls light by a scattering effect in the PDLC film, can be configured without requiring a polarizer and can create a brighter highdefinition picture display with which high optical efficiency is possible. The relationship between the contrast ratio and the optical efficiency of a Schlieren projection system is discussed. To design a projection display with both high brightness and a high contrast ratio, the scattering characteristics of a reflection-mode PDLC cell is evaluated and the optical efficiency of the total projection system is studied using a simple model with perfect diffusion of a light source. Using these results, we design and prototype PDLC light valves for a full-color display and construct a projection display. We succeed in displaying pictures with a contrast ratio of 80:1 and a brightness greater than 1800 ANSI lumens.

show abstract

Section: Projector Efficiency and Schlieren Opticsmentioning

confidence: 99%

Design and fabrication of a projection display using optically addressed polymer-dispersed liquid crystal light valves

et al. 2000

View full text Add to dashboard Cite

show abstract

“…However, in the curing process of printing, UV radiation with enough energy and radiation intensity should be achieved to guarantee the decomposition of the photoinitiator and initiation of the polymerization. [7][8][9][10] If the intensity of UV light is not enough, it may cause incomplete curing, or curing the surface layer only without the interior. This will impact the quality of the printed papers directly.…”

Section: Introductionmentioning

confidence: 99%

UV-LED system to obtain high power density in specific working-plane

Sun

Gou

et al. 2014

SPIE Proceedings

View full text Add to dashboard Cite

With the advantages of low cost, small volume, low energy consumption, long service life and environment friendly, the application of UV-LED has attract widespread concern among academia and industry researchers, especially in the field of ink printing industry. However, how to get high power density in specific distance working plane is a technical problem need to be solved eagerly. This paper presents a design solution to reduce the Etendue of the lighting system and therefore obtain high power density. The design uses UV-LED array as the light source, and uses a freeform surface collimating lens array to collimate this light source. In order to improve the energy sufficiency of the system, multipoint fitting-based freeform surface lens design for UV-LED extended sources is proposed to design collimating free-form lens for UV-LED extended source in this work. The freeform surface collimating lens array is placed in front of the UV-LED extended sources array. And an aspherical lens is used in the optical path to focus the light beam. In the simulation, a light source module with the size of 9mm * 26mm has been designed, and obtained power density up to 8W/cm 2 in the specific working plane with the working-distance of 3cm. This design is expected to replace the existing mercury lamped-based UV light sources and solve the problem in the application of UV-LED ink printing field.Keywords：ink printing industry, UV-LED extended source, optical collimate system, high power density, free form surface * ysy@cigit.ac.cn; +86 023 65935627

show abstract

“…For circular beams output by an ellipsoidal reflector, Area max Solid Angle='rsin2 7niax (1) H 22 sin2 i7…”

Section: Introductionmentioning

confidence: 99%

<title>Metal halide lighting systems and optics for high-efficiency compact LCD projectors</title>

Jacobson

Gengelbach

Stewart

et al. 1998

Projection Displays IV

View full text Add to dashboard Cite

Compact LCD projectors require a high efficiency light source that has the smallest possible spatial extent. Further, they require optical systems that preserve the étendue. Current projector illumination systems have aberrations that produce a light beam whose étendue far exceeds the intrinsic étendue of the light source itself. As a result both efficiency and uniformity fall short of what is theoretically possible. We provide a theoretical framework for understanding these aberrations and the magnitude of their effect. We also present results showing the efficiency, uniformity, and other performance gains which are possible when these aberrations are corrected This work also describes the performance of long-life, short-arc metal halide lighting systems that are able to increase screen brightness of compact projectors several fold without any increase in system power or heat. With these systems it has been possible to design and validate lamps operating at 50Watts, producing >3,000 lumens and having excellent lumen maintenance throughout their 4,000 hour life. The benefits of the combination of an improved dtendue-preserving optical system and a short-arc metal halide lamp will be demonstrated.

show abstract

<title>Light collection efficiency for light valve projection systems</title>

Cited by 31 publications

References 0 publications

Design and fabrication of a projection display using optically addressed polymer-dispersed liquid crystal light valves

Design and fabrication of a projection display using optically addressed polymer-dispersed liquid crystal light valves

UV-LED system to obtain high power density in specific working-plane

<title>Metal halide lighting systems and optics for high-efficiency compact LCD projectors</title>

Contact Info

Product

Resources

About