Spatial light modulator data refresh without tearing artifacts
AssigneeIntel Corporation
InventorSamson Huang
Life of this patent
Estimating the term…
Abstract
A pulse width modulation driven display such as a spatial light modulator, which updates pixel data between PWM periods of consecutive frames, to avoid tearing artifacts in the perceived display image.
Drawings
Claims29
A spatial light modulator for receiving pixel data values from a data source and modulating input light from a light source to output modulated light to a display, the spatial light modulator comprising:
- a frame buffer to store the pixel data values;
- a pixel display array including a plurality of pixel cells to modulate the input light according to the pixel data values in the frame buffer;
- and
- control logic including,
- a pulse width modulator for providing a PWM signal to the pixel display array, the PWM signal including, during a frame,
- a first period during which the PWM signal is forced on,
- a PWM period during which perceived brightness of a pixel cell is determined, and
- a second period during which the PWM signal is forced off, and
- an update controller for enabling the frame buffer to store the pixel data values during the second period of a current frame and the first period of a next frame.
An apparatus comprising:
- means for performing pulse width modulation of a display pixel during a PWM period of a current frame according to pixel data values from a frame buffer;
- and
- means for updating pixel data values in the frame buffer during a period between an end of 5 the PWM period of the current frame and a start of a PWM period of a next frame and including at least a portion of the next frame.
A method of performing pulse width modulation of a display pixel cell by driving the pixel display cell according to a PWM signal, the method comprising:
- (1) for each pixel cell of a plurality of pixel cells in a pixel cell array,
- (1.1) during a first period at the start of a frame, forcing the PWM signal on,
- (1.2) during a PWM period after the first period, executing a PWM transfer curve to determine a brightness of the display pixel cell as indicated by a respective pixel data value in a frame buffer corresponding to the pixel cell, and
- (1.3) during a second period after the PWM period, forcing the PWM signal off;
- and
- (2) during the second period of a current frame and at least a portion of the first period of a next frame, updating pixel data values in the frame buffer.
A method of operating a spatial light modulator which includes a pixel display array, the method comprising:
- during a first period, pulse width modulating a PWM signal to set brightnesses of pixels in the pixel display array according to respective pixel data values in a frame buffer;
- and
- during a second period substantially not overlapping the first period and including portions of a current frame period and a next frame period, updating the pixel data values.
Dependencies are inferred from the claim text.