Projector with UV light source

• US 6,769,773 B1
• Filed: 05/20/2003
• Issued: 08/03/2004
• Est. Priority Date: 05/20/2003
• Status: Active Grant

• Current Assignee: Cheng Kung Capital LLC (Intellectual Ventures LLC)
• Original Assignee: Jiahn-Chang Wu
• Inventors: Wu, Jiahn-Chang
• Primary Examiner(s): Adams, Russell
• Assistant Examiner(s): SEVER, ANDREW T
• Application Number:
  US10/441,363
• Time in Patent Office: 441 Days
• Field of Search: 353/122, 353/30-34, 353/81, 353/84, 353/94, 353/82, 349/5, 349/7-9
• US Class Current: 353/33
• CPC Class Codes: H04N 9/3105 for displaying all colours simultaneously, e.g. by using two or more electronic spatial light modulators simultaneous projection in colour photography G03B33/10; beam splitting or combining systems per se G02B27/10
• CPC Class Codes: H04N 9/3164 using multiple light sources

Abstract

One or more UV light emitting diode (LED) chip is used as the light source of a picture projection system. The UV LED light is converted into red, green and blue light beams by means of red, green and blue fluorescent plates, respectively. The lights emerging from said fluorescent plates is transmitted through one or more programmable liquid crystal plate or reflected by one or more digital micro-mirror device (DMD) to control the light transmission, and then merged together for projection onto a screen. When only one programmable liquid plate or one DMD is used, the different color signals are sequentially projected onto the screen.

Claims

1. A picture projection system comprising:

a light source having at least one ultraviolet (UV) light emitting diode (LED)chip;

a red fluorescent plate for emitting red light beam at the absorption of said UV light, a green fluorescent plate for emitting green light beam at the absorption of said UV light, and a blue fluorescent plate for emitting blue light beam at the absorption of said UV light;

a programmable control means to control the amount of transmitted light from each one of said red light, said green light and said blue light;

merging and focusing means to project the transmitted light onto a projection screen,

wherein said control means is a programmable liquid crystal plate, and

wherein one said UV LED chip each is placed behind cash said red fluorescent plate, said green fluorescent plate, and said blue fluorescent plate;

a first prism to deflect said red light beam before a first said programmable control means,

a second prism to defect said blue light beam before a second said programmable control means;

a third said programmable control means the path of said green light beam;

a first focusing lens system for focusing said red light beam from said first programmable control means onto said projection screen;

a first focusing lens system for focusing said red fight beam from said first programmable control means onto said projection screen;

a second focusing lens system for focusing said blue light beam from said second programmable control means onto said projection screen; and

a third focusing lens system for focusing said green light beam from said third programmable control means onto to said projection screen.

2. The picture projection system as described in claim 1 further comprising:

a third prism to deflect said red light beam after said first programmable liquid crystal plate toward a common focusing lens In for projecting onto said projection screen; and

a fourth prism to deflect said blue light beam after said second programmable liquid crystal plate toward a common focusing lens system for projecting onto said projection screen.