Full color sequential image projection system incorporating time modulated illumination
DCFirst Claim
1. A system for directing intensity modulated electromagnetic energy comprising:
- an intensity modulated light source modulated in intensity in accordance with a predetermined intensity modulation scheme in which a frame interval comprises a plurality of field periods each associated with a different intensity;
a spatial light modulator for directing light from said source, said spatial light modulator including and array of energy directing elements, selected ones of said elements being selectively activated during each of the field periods in synchronism with said predetermined modulation scheme; and
a timing and control circuit to selectively activate the selected elements of said spatial light modulator in response to a first signal representative of data within a single said frame interval and further operable to modulate said source in response to a second signal representative of individual said field periods within said single frame interval,wherein the first and second signals are synchronized to provide an overall system dynamic range greater than an effective dynamic range associated with said spatial light modulator.
0 Assignments
Litigations
0 Petitions
Accused Products
Abstract
A system and technique for directing intensity modulated electromagnetic energy. The inventive system (10) includes an intensity modulated source of electromagnetic energy (12). Individual elements (22) in an array of energy directing elements (15) are activated in sync with the modulation of energy source (12). In a particular implementation, the source (12) is a laser. The intensity of the laser is reduced during each successive field per frame. The energy directing elements (15), in this case--light directing elements, are implemented with an array of digital micromirrors. The light source (12) is modulated in intensity in accordance with a fixed modulation scheme. The mirrors (22) are selectively activated relative to the light source modulation scheme. Hence, the invention provides a gray scale output while allowing the time between mirror flips to be constant. This allows the system clocks to run synchronously and greatly simplifies the writing of data into the display as the time available for writing each bit is constant.
78 Citations
11 Claims
-
1. A system for directing intensity modulated electromagnetic energy comprising:
-
an intensity modulated light source modulated in intensity in accordance with a predetermined intensity modulation scheme in which a frame interval comprises a plurality of field periods each associated with a different intensity; a spatial light modulator for directing light from said source, said spatial light modulator including and array of energy directing elements, selected ones of said elements being selectively activated during each of the field periods in synchronism with said predetermined modulation scheme; and a timing and control circuit to selectively activate the selected elements of said spatial light modulator in response to a first signal representative of data within a single said frame interval and further operable to modulate said source in response to a second signal representative of individual said field periods within said single frame interval, wherein the first and second signals are synchronized to provide an overall system dynamic range greater than an effective dynamic range associated with said spatial light modulator. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9)
-
-
10. A full color sequential image projection system comprising:
-
first, second and third intensity modulated light sources, each said source being modulated in intensity by a predetermined intensity modulation scheme in which a frame interval comprises a plurality of field periods each associated with a different combination of intensity and source; a spatial light modulator for sequentially directing intensity modulated light from each of said sources, said spatial light modulator including an array of light directing elements, selected ons of said light directing elements being selectively activated during each of the field periods in synchronism with said predetermined modulation scheme; a timing and control circuit to selectively activate the selected elements of said spatial light modulator in response to a first signal representative of data within a single said frame interval and further operable to selectively activate each of said sources in response to a respective second signal representative of individual said field periods within said single frame interval; and means for projecting the modulated light directed by said spatial light modulator onto a display surface, wherein the first signal and the second signals are synchronized to provide an overall system dynamic range greater than the dynamic range of said spatial light modulator.
-
-
11. A method for directing energy including the steps of:
-
providing a source of intensity modulated energy of varying intensity to provide a continuum of intensity levels extending from fully off to fully on in accordance with a predetermined intensity modulation scheme, directing the intensity modulated energy onto an array of energy directing elements, modulating said source in response to a first signal representative of said predetermined modulation scheme, selectively activating said energy directing elements in response to a second signal representative of data; and synchronizing the first and second signals to provide an overall system dynamic range greater than the dynamic range of said array.
-
Specification