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Title: Electrochromic projection and writing device

Abstract

A display and projection apparatus includes an electrochromic material and a photoconductive material deposited in tandem used in conjunction with a light filtering means for filtering light transmitted through the electrochromic material. When an electric field is applied across the electrochromic material and the photoconductive material, light that is incident onto the photoconductive material through the surface of the projection apparatus causes the photoconductive material to conduct current locally in proportion to the amount of light incident on the photoconductive material. The flow of current causes the underlying portions of the electrochromic material to switch from an opaque state to a clear or transmissive state, thereby allowing back-light to propagate through the electrochromic material to create a visible image on the surface of the projection apparatus. Reversal of the electric field causes the electrochromic material to revert back to its opaque state, thereby blocking the transmission of back-light and effectively erasing the image from the surface of the projection apparatus.

Inventors:
 [1];  [2]
  1. Boulder, CO
  2. Golden, CO
Issue Date:
Research Org.:
Midwest Research Institute, Kansas City, MO (United States)
OSTI Identifier:
874691
Patent Number(s):
6441942
Assignee:
Midwest Research Institute (Kansas City, MO)
Patent Classifications (CPCs):
G - PHYSICS G02 - OPTICS G02F - DEVICES OR ARRANGEMENTS, THE OPTICAL OPERATION OF WHICH IS MODIFIED BY CHANGING THE OPTICAL PROPERTIES OF THE MEDIUM OF THE DEVICES OR ARRANGEMENTS FOR THE CONTROL OF THE INTENSITY, COLOUR, PHASE, POLARISATION OR DIRECTION OF LIGHT, e.g. SWITCHING, GATING, MODULATING OR DEMODULATING
DOE Contract Number:  
AC36-83CH10093
Resource Type:
Patent
Country of Publication:
United States
Language:
English
Subject:
electrochromic; projection; writing; device; display; apparatus; material; photoconductive; deposited; tandem; conjunction; light; filtering; means; transmitted; electric; field; applied; incident; surface; causes; conduct; current; locally; proportion; amount; flow; underlying; portions; switch; opaque; transmissive; allowing; back-light; propagate; create; visible; image; reversal; revert; blocking; transmission; effectively; erasing; electric field; conductive material; light transmitted; electrochromic material; /359/

Citation Formats

Branz, Howard M, and Benson, David K. Electrochromic projection and writing device. United States: N. p., 2002. Web.
Branz, Howard M, & Benson, David K. Electrochromic projection and writing device. United States.
Branz, Howard M, and Benson, David K. Tue . "Electrochromic projection and writing device". United States. https://www.osti.gov/servlets/purl/874691.
@article{osti_874691,
title = {Electrochromic projection and writing device},
author = {Branz, Howard M and Benson, David K},
abstractNote = {A display and projection apparatus includes an electrochromic material and a photoconductive material deposited in tandem used in conjunction with a light filtering means for filtering light transmitted through the electrochromic material. When an electric field is applied across the electrochromic material and the photoconductive material, light that is incident onto the photoconductive material through the surface of the projection apparatus causes the photoconductive material to conduct current locally in proportion to the amount of light incident on the photoconductive material. The flow of current causes the underlying portions of the electrochromic material to switch from an opaque state to a clear or transmissive state, thereby allowing back-light to propagate through the electrochromic material to create a visible image on the surface of the projection apparatus. Reversal of the electric field causes the electrochromic material to revert back to its opaque state, thereby blocking the transmission of back-light and effectively erasing the image from the surface of the projection apparatus.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {2002},
month = {1}
}

Patent:

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