Dual and multi-modulator projector display systems and techniques are disclosed. In one embodiment, a projector display system comprises a light source; a controller, a first modulator, receiving light from the light source and rendering a halftone image of said the input image; a blurring optical system that blurs said halftone image with a Point Spread Function (PSF); and a second modulator receiving the blurred halftone image and rendering a pulse width modulated image which may be projected to form the desired screen image. Systems and techniques for forming a binary halftone image from input image, correcting for misalignment between the first and second modulators and calibrating the projector system—e.g. over time—for continuous image improvement are also disclosed.

A display apparatus of the present disclosure includes: a first optical system that generates illumination light whose light emitting luminance is variable; a light modulation unit that transmits the illumination light from the first optical system and whose transmissivity is variable; a second optical system that includes a light modulation device and optically modulates the illumination light from the first optical system by using a pulse width modulation technology, the illumination light having passed through the light modulation unit; and a control unit that controls the light emitting luminance of the illumination light from the first optical system and the transmissivity of the light modulation unit in any combination.

Dual and multi-modulator projector display systems and techniques are disclosed. In one embodiment, a projector display system comprises a light source; a controller, a first modulator, receiving light from the light source and rendering a halftone image of said the input image; a blurring optical system that blurs said halftone image with a Point Spread

Function (PSF); and a second modulator receiving the blurred halftone image and rendering a pulse width modulated image which may be projected to form the desired screen image. Systems and techniques for forming a binary halftone image from input image, correcting for misalignment between the first and second modulators and calibrating the projector system—e.g. over time—for continuous image improvement are also disclosed.

Each projection apparatus in a multi-projection system has a liquid crystal panel, a driving circuit configured to perform PWM control of the liquid crystal panel, and a projection image processing unit configured to perform edge blending processing to perform compositing display by each projection apparatus and processing to change gain properties of the edge blending processing by each projection apparatus. Synchronization of each projection apparatus is maintained by a synchronization circuit. Therefore, a sum of image gain in a region of image compositing by each projection apparatus is 1, and the position and image gain properties of the compositing region are changed for each frame, so the position of image deterioration changes for each frame.

A digital light projector having a plurality of color channels including at least one visible color channel providing visible light and at least one invisible color channel providing invisible light. The digital light projector including a projecting device projecting light from the plurality of color channels onto an environment in the form of an array of pixels which together form a video image including a visible image and an invisible image, the video image comprising a series of frames with each frame formed by the array of pixels, wherein to form each pixel of each frame the projecting device sequentially projects a series of light pulses from light provided by each of the plurality of color channels, with light pulses from the at least one visible color channel forming the visible image and light pulses from the at least one invisible color channel forming the invisible image.

Techniques for reducing blend artifacts in a multiple digital projector system are provided, including a first and second projector, having respective projection fields which overlap in a blend zone and one or more control devices configured to: for a given pixel of a common image frame projected by both the first projector and the second projector in the blend zone, the given pixel of the common image frame comprising a plurality of bitplanes arranged in a sequence, control the first projector to project a first portion of the plurality of bitplanes according to the sequence; and control the second projector to project a second portion of the plurality of bitplanes according to the sequence, the second portion complementary to the first portion, such that in the common image frame only one of the first projector and the second projector projects any given bitplane of the plurality of bitplanes.

For an example method of reducing diffraction artifacts in a displayed image from a digital image projection system, a digital controller is coupled to a spatial light modulator. The spatial light modulator includes a two dimensional array of pixels. The method includes receiving signals containing pixel image data and processing the pixel image data to determine a desired gray scale for a pixel. The desired gray scale is compared to achievable gray scales of the digital image projection system. An upper bounding achievable gray scale is determined, and a lower bounding achievable gray scale is determined. Also, a dithering percentage for the desired gray scale is determined. The method chooses one of the upper bounding achievable gray scale and the lower bounding achievable gray scale. Also, a modified lower bounding gray scale is chosen to reduce the dithering percentage.

The present disclosure provides a display device and a control method thereof. The control method of the display device comprises: obtaining, based on the first light output ratio and the second light output ratio, a first luminous flux set composed of values of luminous fluxes output by a combination path at a current bit depth, and a second luminous flux set composed of values of luminous fluxes output by the combination path at a target bit depth respectively; obtaining, based on the first luminous flux set and the second luminous flux set, a value of a luminous flux to be expanded to achieve the target bit depth at the current bit depth; and adjusting a mapping relationship between the value of each luminous flux to be expanded and a value of a maximum luminous flux in the first luminous flux set corresponding to the current bit depth based on a display bit depth of the display device.

A semiconductor light source driving device includes: a switching power supply circuit that converts a voltage across direct current (DC) power supply into a DC output voltage and outputs the DC output voltage to a semiconductor light source; and a light source driving circuit connected in series to the semiconductor light source. The switching power supply circuit includes: a switching circuit; an output capacitor; a controller; and an inductor short circuit. The switching circuit includes: a first switching element for voltage control; a second switching element connected in series to the first switching element; and an inductor connected to a connection point between the first and second switching elements. The inductor short circuit includes a diode and a fourth switching element connected in series to the diode.

Provided is an apparatus that includes an image projection section that performs an image projection process based on a PWM method, an output image control section that sets a portion of a single-frame output period of a view-use image as a period in which to output a pattern image to be used for calculating an image correction parameter, a correction parameter calculation section that calculates the image correction parameter with use of the pattern image captured by a camera in the pattern image output period, and an image correction section that performs a correction process on the view-use image with use of the image correction parameter. The output image control section controls the pattern image output period in such a manner that pixel values of the pattern image fall within a range from a minimum pixel value to less than a minimum significant pixel value of the view-use image.