Televisions and other types of displays are pervasive in today's society. Recent years have seen the introduction of higher definition displays. Engineers continue to try to increase the resolution of displays to provide better picture quality, but also face constraints associated with providing such increased resolution.
One approach for increasing the resolution of a display involves increasing a perceived resolution of a display by a user. Rather than providing more pixels, a first image is displayed including a set number of pixels corresponding to the same number of sample data points of the image to be displayed. Then at a time period very close to the display of the first image, a second image is displayed including the same number of pixels but with slightly different sample points of the image. This second image on the display is offset by a small amount from the display of the first image. The human eye perceives both images as being displayed at the same time, resulting in an effective doubling of the display resolution. This technique is referred to in the industry by many names including modulation, optical dithering, and SmoothPicture™.
In one technique for effecting the offset of the two images, a mirror is used as an optical dithering element to direct light corresponding to pixels to be displayed onto the display. The mirror is repeatedly switched from one position to another such that the first position of the mirror corresponds to a display of an unshifted image and the second position corresponds to a display of a shifted image. Thus rapid positioning of the mirror between the first and second positions allows an increase in the perceived resolution of the display.
In order to control the position of an optical dithering element, it is useful to measure the position of the optical dithering element. However, such a measurement can often be costly, adding undue expense to the underlying product.