Patent JPS556361A successfully refreshed from Google Patents.
Patent US6064366A successfully refreshed from Google Patents.
US6064366A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Spatial light modulators
Assignee: RANK NEMO (DPL) Ltd (FORMERLY DIGITAL PROJECTION LIMITED)
•
Filing: 1997-06-03
•
Granted: 2000-05-16
•
Expires: 2017-06-03
Abstract
Abstract A spatial light modulator in the form of a deformable mirror device (110) receives from a frame store (116) data which has been formatted by a data formatter (114) subsequent to gamma correction in a ROM look-up table (112). The DMD (110) displays different light levels by being ON for selected periods of a series of durations 4, 8, 16 . . . 1024 varying in proportion to a basic period multiplied by powers of two. The shortest duration 4 for which the DMD can be turned on is a multiple of the basic period, and the series includes additional durations 5, 6 and 7 in the series between the shortest displayable duration 4 and the next power of two 8. Durations 1, 2 and 3 of less than the shortest displayable duration can be displayed by adjusting the turn-on time of a proportion of the adjacent mirrors. The longest duration for which the mirror can be turned on can be employed twice.
Inventors
- 👤 John David Millward
- 👤 John Gillespie
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 12:07
CPC Classifications
G; G09; G09G; G09G3/00; G09G3/20; G09G3/34; G09G3/3433; G09G3/346; H; H04; H04N; H04N5/00; H04N5/74; H04N5/7416; H04N5/7458; H04N9/00; H04N9/12; H04N9/31; H04N9/3102; H04N9/312; H04N9/3129; H04N9/3141; H04N9/315; H04N9/3164; H04N9/3179; H04N9/3188; G09G2300/00; G09G2300/08; G09G2320/00; G09G2320/02; G09G2320/0271; G09G2320/0276; G09G3/2007; G09G3/2018; G09G3/2022; G09G3/2037; G09G3/2059; H04N2005/7466; H04N9/64; H04N9/68; H04N9/69
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
159 words
A spatial light modulator comprising: an array of deformable mirror elements; and control circuitry for applying control signals to the individual mirror elements of the array such that the mirror elements are selectively switchable between "ON" and "OFF" orientations, each mirror element being "ON" for a chosen duration varying substantially in proportion to integer multiples of a basic period determined by the control signals so as to display a chosen light level, each of the mirror elements having a minimum "ON" duration which is greater than the basic period, said control circuitry being arranged such that light levels corresponding to durations of less than the minimum "ON" duration for any particular mirror elements are displayed by setting the control signals to the particular mirror elements to produce zero "ON" durations and modifying the control signals to a proportion of the other mirror elements in the array to increase the "ON" durations of said proportion of the other mirror elements.
Claim 2
Dependent Claim
159 words
A spatial light modulator comprising: an array of deformable mirror elements; and control circuitry for applying control signals to the individual mirror elements of the array such that the mirror elements are selectively switchable between "ON" and "OFF" orientations, each mirror element being "ON" for a chosen duration varying substantially in proportion to integer multiples of a basic period determined by the control signals so as to display a chosen light level, each of the mirror elements having a minimum "ON" duration which is greater than the basic period, said control circuitry being arranged such that light levels corresponding to durations of less than the minimum "ON" duration for any particular mirror elements are displayed by setting the control signals to the particular mirror elements to produce zero "ON" durations and modifying the control signals to a proportion of the other mirror elements in the array to increase the "ON" durations of said proportion of the other mirror elements.
Claim 3
Dependent Claim
26 words
A modulator according to claim 1, in which the proportion of mirror elements are one or more adjacent mirror elements to each said particular mirror element.
Claim 4
Dependent Claim
34 words
A modulator according to claim 2, in which there are three separate arrays of deformable mirror elements, each designed to reflect light of a different color, and the modified control signals are luminance values.
Claim 5
Dependent Claim
182 words
A display apparatus comprising: a light source; and at least one spatial light modulator comprising: an array of deformable mirror elements; means for directing light from the light source onto the spatial light modulator; and control circuitry for applying control signals to the individual mirror elements of the array such that the mirror elements are selectively switchable between "ON" and "OFF" orientations, each mirror element being "ON" for a chosen duration varying substantially in proportion to integer multiples of a basic period determined by the control signals so as to display a chosen light level, each of the mirror elements having a minimum "ON" duration which is greater than the basic period, said control circuitry being arranged such that light levels corresponding to durations of less than the minimum "ON" duration for any particular mirror elements are displayed by setting the control signals to the particular mirror elements to produce zero "ON" durations and modifying the control signals to a proportion of the other mirror elements in the array to increase the "ON" durations of said proportion of the other mirror elements.
Claim 6
Dependent Claim
182 words
A display apparatus comprising: a light source; and at least one spatial light modulator comprising: an array of deformable mirror elements; means for directing light from the light source onto the spatial light modulator; and control circuitry for applying control signals to the individual mirror elements of the array such that the mirror elements are selectively switchable between "ON" and "OFF" orientations, each mirror element being "ON" for a chosen duration varying substantially in proportion to integer multiples of a basic period determined by the control signals so as to display a chosen light level, each of the mirror elements having a minimum "ON" duration which is greater than the basic period, said control circuitry being arranged such that light levels corresponding to durations of less than the minimum "ON" duration for any particular mirror elements are displayed by setting the control signals to the particular mirror elements to produce zero "ON" durations and modifying the control signals to a proportion of the other mirror elements in the array to increase the "ON" durations of said proportion of the other mirror elements.
Claim 7
Dependent Claim
24 words
A display apparatus according to claim 4, including a projection screen on which light spatially modulated by the spatial light modulator may be projected.
Claim 8
Dependent Claim
35 words
A display apparatus according to claim 4, further comprising: means for inputting a gamma corrected video signal; degamma circuitry for removing the degamma correction; and means for deriving said control signals from said video signal.
Claim 9
Dependent Claim
166 words
An address system for a spatial light modulator having an array of deformable mirror elements, the address system comprising: control circuitry for applying control signals to the individual mirror elements of the array such that the mirror elements are selectively switchable between "ON" and "OFF" orientations, each mirror element being "ON" for a chosen duration varying substantially in proportion to integer multiples of a basic period determined by the control signals so as to display a chosen light level, each of the mirror elements having a minimum "ON" duration which is greater than the basic period, said control circuitry being arranged such that light levels corresponding to durations of less than the minimum "ON" duration for any particular mirror elements are displayed by setting the control signals to the particular mirror elements to produce zero "ON" durations and modifying the control signals to a proportion of the other mirror elements in the array to increase the "ON" durations of said proportion to the other mirror elements.
Claim 10
Dependent Claim
166 words
An address system for a spatial light modulator having an array of deformable mirror elements, the address system comprising: control circuitry for applying control signals to the individual mirror elements of the array such that the mirror elements are selectively switchable between "ON" and "OFF" orientations, each mirror element being "ON" for a chosen duration varying substantially in proportion to integer multiples of a basic period determined by the control signals so as to display a chosen light level, each of the mirror elements having a minimum "ON" duration which is greater than the basic period, said control circuitry being arranged such that light levels corresponding to durations of less than the minimum "ON" duration for any particular mirror elements are displayed by setting the control signals to the particular mirror elements to produce zero "ON" durations and modifying the control signals to a proportion of the other mirror elements in the array to increase the "ON" durations of said proportion to the other mirror elements.
Claim 11
Independent Claim
162 words
A method of displaying an image using a spatial light modulator having an array of deformable mirror elements, comprising: applying control signals to the individual mirror elements of the array such that the mirror elements are selectively switchable between "ON" and "OFF" orientations, each mirror element being "ON" for a chosen duration varying substantially in proportion to integer multiples of a basic period determined by the control signals so as to display a chosen light level, each of the mirror elements having a minimum "ON" duration which is greater than the basic period, the control signals being such that light levels corresponding to durations of less than the minimum "ON" duration for any particular mirror elements are displayed by setting the control signals to the particular mirror elements to produce zero "ON" durations, the control signals to a proportion of the other mirror elements in the array being modified to increase the "ON" durations of said proportion of the other mirror elements.
Claim 12
Independent Claim
162 words
A method of displaying an image using a spatial light modulator having an array of deformable mirror elements, comprising: applying control signals to the individual mirror elements of the array such that the mirror elements are selectively switchable between "ON" and "OFF" orientations, each mirror element being "ON" for a chosen duration varying substantially in proportion to integer multiples of a basic period determined by the control signals so as to display a chosen light level, each of the mirror elements having a minimum "ON" duration which is greater than the basic period, the control signals being such that light levels corresponding to durations of less than the minimum "ON" duration for any particular mirror elements are displayed by setting the control signals to the particular mirror elements to produce zero "ON" durations, the control signals to a proportion of the other mirror elements in the array being modified to increase the "ON" durations of said proportion of the other mirror elements.
Claim 13
Dependent Claim
26 words
A method according to claim 8, in which the proportion of mirror elements are one or more adjacent mirror elements to each said particular mirror element.
Claim 14
Dependent Claim
33 words
A method according to claim 9, in which there are three separate arrays of deformable mirror elements, each designed to reflect light of different color, and the modified control signals are luminance values.
Claim 15
Dependent Claim
150 words
A spatial light modulator comprising: an array of light modulating elements; and control circuitry for applying control signals to the individual elements of the array such that the elements are selectively switchable between "ON" and "OFF" states, each element being "ON" for a chosen duration varying substantially in proportion to integer multiples of a basic period determined by the control signals so as to display a chosen light level, each of the elements having a minimum "ON" duration which is greater than the basic period, said control circuitry being arranged such that light levels corresponding to durations of less than the minimum "ON" duration for any particular elements are displayed by setting the control signals to the particular elements to produce zero "ON" durations and modifying the control signals to a proportion of the other elements in the array to increase the "ON" durations of said proportion of the elements.
Claim 16
Dependent Claim
150 words
A spatial light modulator comprising: an array of light modulating elements; and control circuitry for applying control signals to the individual elements of the array such that the elements are selectively switchable between "ON" and "OFF" states, each element being "ON" for a chosen duration varying substantially in proportion to integer multiples of a basic period determined by the control signals so as to display a chosen light level, each of the elements having a minimum "ON" duration which is greater than the basic period, said control circuitry being arranged such that light levels corresponding to durations of less than the minimum "ON" duration for any particular elements are displayed by setting the control signals to the particular elements to produce zero "ON" durations and modifying the control signals to a proportion of the other elements in the array to increase the "ON" durations of said proportion of the elements.
Claim 17
Dependent Claim
19 words
The spatial light modulator of claim 11 wherein the light modulating elements of the array are liquid crystal devices.
References Cited (Backward Citations)
GB2014822A
Cited
US4680579A
Cited
US4566935A
Cited
US4615595A
Cited
US4783703A
Cited
EP0261901A2
Cited
US5175807A
Cited
US5404427A
Cited
EP0270259B1
Cited
WO1990003023A1
Cited
US5254982A
Cited
EP0391529A2
Cited
US5057919A
Cited
US5157525A
Cited
US5012163A
Cited
US5280277A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2003-05-16 | 2003-11-15 | 2004-05-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2007-05-16 | 2007-11-15 | 2008-05-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2011-05-16 | 2011-11-15 | 2012-05-16 | $7700.00 | Window Closed / Lapsed |