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Screen-door effect

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212:(DLP) projectors can be mitigated by deliberately setting the projected image slightly out of focus, which blurs the boundaries of each pixel to its neighbor. This minimizes the effect by filling the black pixel perimeters with adjacent light. Some older LCD projectors have a more noticeable screen door effect than first generation DLP projectors. Newer DLP chip designs promise closer spacing of the mirror elements which would reduce this effect; however, some space is still required along one edge of the mirror to provide a control circuit pathway. Use of Dolgoff's depixelization method could also produce a DLP projector without noticeable pixelation. 205:
green pixels (appearing bright) adjacent to red and blue pixels (appearing dark), forming a noticeable repeating light and dark pattern. Use of a micro-lens array at a slightly greater distance created new pixel images, with each "new" pixel being a summation of six neighboring sub-pixels (made up of two full color pixels, one above the other). Since there were as many micro-lenses as there were original pixels, no resolution was lost, which was confirmed with modulation transfer function (MTF) measurements.
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array, wherein each micro-lens caused a slightly magnified image of the pixel behind it, filling in the previously-visible spaces between pixels. In addition, when making a projector with a single, full-color LCD panel, an additional appearance of pixelation was visible due to the noticeability of
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than the size of the image they project, enlarging these fine lines, which are much smaller than the pixels themselves, to be seen. This results in an image that appears as if viewed through a fine screen or mesh such as those used on anti-insect
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images and regular displays under magnification or at close range, but the increases in display resolutions have made this much less significant. More recently, the screen door effect has been an issue with
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The screen door effect was noticed on the first digital projector: an LCD projector made in 1984 by Gene Dolgoff. To eliminate this artifact, Dolgoff invented de
226: 281: 200:, which used various optical methods to eliminate the visibility of the spaces between the pixels. The dominant method made use of a 89: 61: 68: 42: 108: 75: 57: 46: 321: 168:, because these are viewed at a much closer distance, and stretch a single display across a much wider 326: 209: 289: 161: 35: 184:
and DLP projectors, SDE can be seen because projector optics typically have significantly lower
82: 263: 165: 8: 242: 232: 306: 156: 221: 140: 315: 185: 169: 197: 190: 237: 201: 123: 24: 148: 152: 144: 181: 229:, an artifact associated with single-chip DLP projectors 49:. Unsourced material may be challenged and removed. 307:Hi Fi Writer, "What is the 'screen door effect'?" 313: 261: 143:of displays, where the fine lines separating 109:Learn how and when to remove this message 122: 127:Demonstration of the screen door effect 314: 175: 47:adding citations to reliable sources 18: 13: 151:) become visible in the displayed 14: 338: 300: 23: 262:Greg Kumparak (26 March 2014). 34:needs additional citations for 282:"Home Theater: dlp versus lcd" 274: 255: 1: 288:. 18 May 2004. Archived from 248: 7: 264:"A Brief History Of Oculus" 215: 16:Visual artifact of displays 10: 343: 208:The screen door effect on 210:Digital Light Processing 162:virtual reality headsets 155:. This can be seen in 128: 166:head-mounted displays 126: 292:on 10 November 2013. 58:"Screen-door effect" 43:improve this article 322:Display technology 243:Subpixel rendering 233:Silk screen effect 133:screen-door effect 129: 176:SDE in projectors 157:digital projector 119: 118: 111: 93: 334: 327:Visual artifacts 294: 293: 278: 272: 271: 259: 222:Apple Vision Pro 114: 107: 103: 100: 94: 92: 51: 27: 19: 342: 341: 337: 336: 335: 333: 332: 331: 312: 311: 303: 298: 297: 280: 279: 275: 260: 256: 251: 218: 178: 141:visual artifact 115: 104: 98: 95: 52: 50: 40: 28: 17: 12: 11: 5: 340: 330: 329: 324: 310: 309: 302: 301:External links 299: 296: 295: 273: 253: 252: 250: 247: 246: 245: 240: 235: 230: 227:Rainbow effect 224: 217: 214: 177: 174: 117: 116: 31: 29: 22: 15: 9: 6: 4: 3: 2: 339: 328: 325: 323: 320: 319: 317: 308: 305: 304: 291: 287: 283: 277: 269: 265: 258: 254: 244: 241: 239: 236: 234: 231: 228: 225: 223: 220: 219: 213: 211: 206: 203: 199: 194: 192: 187: 186:pixel density 183: 173: 171: 170:field of view 167: 163: 158: 154: 150: 146: 142: 138: 134: 125: 121: 113: 110: 102: 91: 88: 84: 81: 77: 74: 70: 67: 63: 60: –  59: 55: 54:Find sources: 48: 44: 38: 37: 32:This article 30: 26: 21: 20: 290:the original 285: 276: 267: 257: 207: 198:pixelization 195: 191:screen doors 179: 136: 132: 130: 120: 105: 96: 86: 79: 72: 65: 53: 41:Please help 36:verification 33: 316:Categories 286:AllExperts 268:TechCrunch 249:References 164:and other 99:March 2014 69:newspapers 238:Scan line 202:microlens 149:subpixels 216:See also 139:) is a 83:scholar 145:pixels 85:  78:  71:  64:  56:  153:image 90:JSTOR 76:books 147:(or 131:The 62:news 182:LCD 180:In 137:SDE 45:by 318:: 284:. 266:. 193:. 172:. 270:. 135:( 112:) 106:( 101:) 97:( 87:· 80:· 73:· 66:· 39:.

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"Screen-door effect"
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visual artifact
pixels
subpixels
image
digital projector
virtual reality headsets
head-mounted displays
field of view
LCD
pixel density
screen doors
pixelization
microlens
Digital Light Processing
Apple Vision Pro
Rainbow effect
Silk screen effect
Scan line

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