Looking for breakthrough ideas for innovation challenges? Try Patsnap Eureka!

Method of representing a video image by means of a projector

A technology of video images and projectors, which is applied in the direction of using projection devices, image reproducers, image communications, and parts of color TVs, and can solve problems such as short life expectancy

Inactive Publication Date: 2006-02-22
SIGNIFY HLDG BV
View PDF5 Cites 3 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Increased frequency of alternating current results in shorter lamp life expectancy

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Method of representing a video image by means of a projector
  • Method of representing a video image by means of a projector

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0021] figure 1 is a time diagram with a square-wave pulsating alternating current 10, the period of which has a duration of T0. The square-wave pulsating alternating current 10 is composed of a square-wave alternating current IR and a pulsating current IP. T0 is equal to 16 ms, or a video frequency of 60 Hz as used in NTSC video systems. The first pulse P1 ends at instant t1, ie after half a period before inversion. This square-wave pulsating alternating current 10 comprises a second pulse P2 which ends at time t2, ie after a quarter of a period. The magnitude of this square-wave alternating current IR is denoted I2. The pulses P1 and P2 are components of the pulsating current IP with pulse durations tP1 and tP2, amplitude I3 and the same profile. When an alternating current IR and a pulsating current IP having the same polarity are superimposed, the result is a pulsating square-wave alternating current I0 whose highest amplitude is I4. A total of four pulses P1, P2, P3 ...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

No PUM Login to View More

Abstract

The invention relates to a method of representing a video image based on a video signal by means of a projector which comprises an image display device and a high-pressure gas discharge lamp, which lamp is supplied with a square-wave alternating current (I 0 , I 10 ) on which a current pulse (P 1 , P 3 , P 10 , P 40 ) is superimposed before each phase reversal. According to the invention, the alternating current (I 0 , I 10 ) is superimposed with a second current pulse (P 2 , P 4 , P 20 , P 30 , P 50 , P 60 ) of the same polarity. A simple attunement of the alternating current frequency to the image frequency without image artifacts is made possible by the second pulses (P 2 , P 4 , P 20 , P 30 , P 50 , P 60 ).

Description

technical field [0001] The invention relates to a method for representing a video image based on a video signal using a projector comprising an image display device and a high-pressure gas discharge lamp supplied with a square-wave alternating current, current pulses being superimposed before each phase inversion on it. Background technique [0002] Projectors with such image display devices known as light valves and arrays are known from DE 69424858T2 and EP 1154652 . The structural principle is explained in detail below. [0003] It is known from EP 1152645 A1 how a high-pressure gas discharge lamp can be operated with a square-wave alternating current of such a projector. Before the inversion at the end of each half cycle of the lamp current, ie before the polarity change, the alternating current is superimposed with current pulses of the same polarity. This avoids leap ing of the luminous discharge arc and flickering of the image. However, this current change has the...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
IPC IPC(8): H04N9/31
CPCH04N9/3114H04N9/315H05B41/2928Y02B20/202H05B41/3928Y02B20/00H04N9/31
Inventor H·门希C·德佩X·里德雷尔E·G·韦泽尔N·H·G·赖恩德尔斯
Owner SIGNIFY HLDG BV
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Patsnap Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Patsnap Eureka Blog
Learn More
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic, Popular Technical Reports.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap|About US| Contact US: help@patsnap.com