Larry J. Hornbeck

Characteristics Of The Deformable Mirror Device For Optical Information Processing

A new two-dimensional, fast, analog, electrically addressable, silicon-based membrane spatial light modulator (SLM) has been developed for optical information processing applications. This SLM, the deformable mirror device (DMD), consists of a 128x128 array of deformable mirror elements addressed by an underlying array of metal-oxide-semiconductor (MOS) transistors. Coherent light reflected from the mirror elements is phase modulated producing an optical Fourier transform of an analog signal input to the device. The DMD architecture and operating parameters related to this application are presented. A model is developed that describes the optical Fourier transform properties of the DMD. The calculated peak first-order diffraction efficiency of 8.2% is in good agreement with the value of 8.4% obtained from experimental optical Fourier transform measurements.

Current status of the digital micromirror device (DMD) for projection television applications

This paper describes recent advances in digital micromirror device (DMD) technology for projection television (PTV) applications, including a new device called the hidden hinge DMD with improved optical efficiency and contrast ratio. The DMD is a micromechanical, reflective spatial light modulator monolithically fabricated over a conventional CMOS SRAM address circuit. A 768/spl times/576 pixel array DMD (442,368 mirrors) has been developed for and demonstrated in one-DMD and three-DMD PTV systems having diagonals ranging in size from 42 inches to 13 feet.<<ETX>>

Digital Light Processing for high-brightness high-resolution applications

Electronic projection display technology for high-brightness applications had its origins in the Gretag Eidophor, an oil film-based projection system developed in the early 1940s. A number of solid state technologies have challenged the Eidophor, including CRT-addressed LCD light valves and active-matrix-addressed LCD panels. More recently, in response to various limitations of the LCD technologies, high-brightness systems have been developed based on Digital Light Processing technology. At the heart of the DLP projection display is the Digital Micromirror Device, a semiconductor-based array of fast, reflective digital light switches that precisely control a light source using a binary pulsewidth modulation technique. This paper describes the design, operation, performance, and advantages of DLP- based projection systems for high-brightness, high- resolution applications. It also presents the current status of high-brightness products that will soon be on the market.

Deformable-Mirror Spatial Light Modulators

A brief overview of deformable-mirror spatial light modulator (SLM) technology is presented, followed by the first comprehensive review of the Texas Instruments deformable-mirror device (DMD), a subclass of deformable-mirror SLMs. The DMD architecture, fabrication, and operation (both analog and digital) are described. It is shown that amplitude-dominant or phase-dominant modulation is obtained by a simple modification of the pixel architecture. Representative DMD applications are presented.

Digital Light Processing and MEMS: an overview

A new projection display technology called Digital Light Processing/sup TM/ (DLP/sup TM/) accepts digital video and transmits to the eye a burst of digital light pulses that the eye interprets as a color analog image. DLP is based on a microelectromechanical systems (MEMS) device known as the Digital Micromirror Device/sup TM/ (DMD/sup TM/). Invented in 1987 at Texas Instruments, the DMD is a fast, reflective digital light switch. It can be combined with image processing, memory, a light source, and optics to form a DLP system capable of projecting large, bright, seamless, high-contrast color images with better color fidelity and consistency than current displays.

Digital Light Processing and MEMS: reflecting the digital display needs of the networked society

Digital video technology is becoming increasingly important to the networked society. The natural interface to digital video is a digital display, one that accepts electrical bits at its input and converts them into optical bits at the output. The digital-to-analog processing function is performed in the mind of the observer. Texas Instruments has developed such a display with its recent market introduction of the Digital Light ProcessingTM (DLPTM) projection display. DLP technology is based on the Digital Micromirror DeviceTM (DMDTM), a microelectromechanical systems (MEMS) array of semiconductor-based digital light switches. The DMD switching array precisely controls a light source for projection display and digital printing applications. This paper presents an overview of DLP technology along with the architecture, projection operation, manufacture, and reliability of the DMD. Features of DMD technology that distinguish it from conventional MEMS technology are explored. Finally, the paper provides a view of DLP business opportunities.

Projection displays and MEMS: timely convergence for a bright future

Projection displays and microelectromechanical systems (MEMS) have evolved independently, occasionally crossing paths as early as the 1950s. But the commercially viable use of MEMS for projection displays has been illusive until the recent invention of Texas Instruments Digital Light Processing TM (DLP) technology. DLP technology is based on the Digital Micromirror DeviceTM (DMD) microchip, a MEMS technology that is a semiconductor digital light switch that precisely controls a light source for projection display and hardcopy applications. DLP technology provides a unique business opportunity because of the timely convergence of market needs and technology advances. The world is rapidly moving to an all- digital communications and entertainment infrastructure. In the near future, most of the technologies necessary for this infrastrucutre will be available at the right performance and price levels. This will make commercially viable an all-digital chain (capture, compression, transmission, reception decompression, hearing, and viewing). Unfortunately, the digital images received today must be translated into analog signals for viewing on todays televisions. Digital video is the final link in the all-digital infrastructure and DLP technoogy provides that link. DLP technology is an enabler for digital, high-resolution, color projection displays that have high contrast, are bright, seamless, and have the accuracy of color and grayscale that can be achieved only by digital control. This paper contains an introduction to DMD and DLP technology, including the historical context from which to view their developemnt. The architecture, projection operation, and fabrication are presented. Finally, the paper includes an update about current DMD business opportunities in projection displays and hardcopy.

Combining Digital Optical MEMS, CMOS and Algorithms for Unique Display Solutions

The binary electrostatic actuation of a MEMS micromirror through relatively large rotation angles by a single, low- voltage SRAM cell forms the basis of a digital optical MEMS switch, or DMD pixel, that is fast, scalable, producible and reliable. Arrays of DMD pixels are monolithically integrated on a CMOS chip and combined with optics, algorithms and a light source to produce unique DLPreg front projection and HDTV products. Examples include DLP pocket-class mobile projectors, 3-D enabled DLP HDTVs and DLP Cinemareg projectors.

Digital Light Processing update: status and future applications

Digital Light Processing (DLP) projection displays based on the Digital Micromirror Device (DMD) were introduced to the market in 1996. Less than 3 years later, DLP-based projectors are found in such diverse applications as mobile, conference room, video wall, home theater, and large-venue. They provide high-quality, seamless, all-digital images that have exceptional stability as well as freedom from both flicker and image lag. Marked improvements have been made in the image quality of DLP-based projection display, including brightness, resolution, contrast ratio, and border image. DLP-based mobile projectors that weighted about 27 pounds in 1996 now weight only about 7 pounds. This weight reduction has been responsible for the definition of an entirely new projector class, the ultraportable. New applications are being developed for this important new projection display technology; these include digital photofinishing for high process speed minilab and maxilab applications and DLP Cinema for the digital delivery of films to audiences around the world. This paper describes the status of DLP-based projection display technology, including its manufacturing, performance improvements, and new applications, with emphasis on DLP Cinema.

21.4: DLP Cinema™ Projectors: Enabling Digital Cinema

Digital Light Processing™ projection displays span the gamut of applications from ultralight to ultrabright. DLP Cinema™ projection displays are the adaptation of conventional DLP™ projectors to meet the requirements of digital cinema. This paper describes DLP Cinema™ prototype projectors and ongoing field demonstrations of these prototypes in eighteen or more theater locations in North America, Europe and Japan.