Wobulation is the known variation ("wobble") in a characteristic. For example, wobulation of advanced radar waveform modulations – where the repetition rate or center frequency of a signal is changed in a repetitive fashion to reduce the probability of interception.
In large-screen television technology, wobulation is Hewlett-Packard's term for a form of interlacing designed for use with fixed pixel displays. The term is loosely derived from the word 'wobble' and was inspired by HP's work with the overlap of printing ink. Wobulation reduces the cost and complexity of components required for the creation of high resolution TVs.
Wobulation works by overlapping pixels. It does so by generating multiple sub-frames of data while an optical image shifting mechanism (e.g. the mirror of a digital micromirror device) then displaces the projected image of each sub-frame by a fraction of a pixel (e.g. one-half or one-third). The sub-frames are then projected in rapid succession, and appear to the human eye as if they are being projected simultaneously and superimposed. For example, a high-resolution HDTV video frame is divided into two sub-frames, A and B. Sub-frame A is projected, and then the miniature mirror on a digital micromirror device switches and displaces sub-frame B one half pixel length as it is projected. When projected in rapid succession, the sub-frames superimpose, and create to the human eye a complete and seamless image. If the video sub-frames are aligned so that the corners of the pixels in the second sub-frame are projected at the centers of the first, the illusion of double the resolution is achieved, like in an interlaced CRT display. Thus a lower resolution fixed pixel device using wobulation can emulate the picture of a higher resolution fixed device, at a reduced cost.
As of 2007[update], wobulation is used only to double the horizontal resolution of a display, unlike CRT interlacing that doubles the vertical resolution. However, it is capable of doubling the vertical and horizontal resolution of an image (2× wobulation).
While wobulation can in theory be used in many types of display devices, it is currently primarily used in displays using Digital Light Processing (DLP). DLP is a Texas Instruments (TI) technology which relies on a Digital Micromirror Device (DMD) chip. TI calls its implementation of wobulation 'SmoothPicture'. Horizontal wobulation used in current TI products allows a DMD chip with a 960×1080 mirror array to produce a 1920×1080 pixel picture; most recent designs employed in 3D DLP sets use "offset-diamond pixel layout", where the mirrors form a "checkerboard pattern" array.[1] Also, the image overlap inherent in the use of wobulation eliminates the 'screen door' effect common on other fixed pixel displays such as plasma and LCD, but may in some implementations also create some reduction in sharpness. Wobulation was used by a number of TV manufacturers, including Hewlett-Packard, Mitsubishi, RCA, Samsung, and Toshiba.
US patent 6078038, J. Carl Cooper, "Apparatus and method for displaying a high resolution image with relatively lower resolution display device", issued 2000-06-20
US patent 7030894, William J. Allen, Mark E. Gorzynski, P Guy Howard, Paul J. McClellan, "Image display system and method", issued 2006-04-18
US patent 7034811, William Allen, "Image display system and method", issued 2006-04-25
wobulation, known, variation, wobble, characteristic, example, wobulation, advanced, radar, waveform, modulations, where, repetition, rate, center, frequency, signal, changed, repetitive, fashion, reduce, probability, interception, large, screen, television, t. Wobulation is the known variation wobble in a characteristic For example wobulation of advanced radar waveform modulations where the repetition rate or center frequency of a signal is changed in a repetitive fashion to reduce the probability of interception In large screen television technology wobulation is Hewlett Packard s term for a form of interlacing designed for use with fixed pixel displays The term is loosely derived from the word wobble and was inspired by HP s work with the overlap of printing ink Wobulation reduces the cost and complexity of components required for the creation of high resolution TVs Wobulation works by overlapping pixels It does so by generating multiple sub frames of data while an optical image shifting mechanism e g the mirror of a digital micromirror device then displaces the projected image of each sub frame by a fraction of a pixel e g one half or one third The sub frames are then projected in rapid succession and appear to the human eye as if they are being projected simultaneously and superimposed For example a high resolution HDTV video frame is divided into two sub frames A and B Sub frame A is projected and then the miniature mirror on a digital micromirror device switches and displaces sub frame B one half pixel length as it is projected When projected in rapid succession the sub frames superimpose and create to the human eye a complete and seamless image If the video sub frames are aligned so that the corners of the pixels in the second sub frame are projected at the centers of the first the illusion of double the resolution is achieved like in an interlaced CRT display Thus a lower resolution fixed pixel device using wobulation can emulate the picture of a higher resolution fixed device at a reduced cost As of 2007 update wobulation is used only to double the horizontal resolution of a display unlike CRT interlacing that doubles the vertical resolution However it is capable of doubling the vertical and horizontal resolution of an image 2 wobulation While wobulation can in theory be used in many types of display devices it is currently primarily used in displays using Digital Light Processing DLP DLP is a Texas Instruments TI technology which relies on a Digital Micromirror Device DMD chip TI calls its implementation of wobulation SmoothPicture Horizontal wobulation used in current TI products allows a DMD chip with a 960 1080 mirror array to produce a 1920 1080 pixel picture most recent designs employed in 3D DLP sets use offset diamond pixel layout where the mirrors form a checkerboard pattern array 1 Also the image overlap inherent in the use of wobulation eliminates the screen door effect common on other fixed pixel displays such as plasma and LCD but may in some implementations also create some reduction in sharpness Wobulation was used by a number of TV manufacturers including Hewlett Packard Mitsubishi RCA Samsung and Toshiba References edit DLP products Texas Instruments US patent 6078038 J Carl Cooper Apparatus and method for displaying a high resolution image with relatively lower resolution display device issued 2000 06 20 US patent 7030894 William J Allen Mark E Gorzynski P Guy Howard Paul J McClellan Image display system and method issued 2006 04 18 US patent 7034811 William Allen Image display system and method issued 2006 04 25 External links editHewlett Packard Wobulation Explanation at Popular Science Retrieved from https en wikipedia org w index php title Wobulation amp oldid 1133071915, wikipedia, wiki, book, books, library,
