Patent Application
20080136794
Disclosed are input devices, electronic devices, and methods for touch input, and more particularly, for integrating photo sensors into sub-pixels of pixels of an array of pixels to substantially maintain the brightness of a display with a touch input.
Manufacturers of electronic products often include touch sensitive user interface devices on their products. In one implementation, a touch sensitive screen may receive input to photo sensors that are positioned with or embedded in a sub-pixel of a pixel of an array of pixels forming a display screen. Such a display is said to be a display with a touch input. Input to a photo sensor can be detected in different manners. For example, a change in the size or location of a shadowed area or a bright area as a function of time may indicate that an object such as finger or stylus is nearing or proximal the touch screen.
Touch sensitive user interface devices and displays are widely used in electronic products, such as communication devices, computer monitors and televisions. These devices and displays provide images as a collection of pixels in which each pixel includes sub-pixels. Pixels are picture elements that are units constituting images. Thus, images may be represented by a collection of discrete pixels. Each pixel may be subdivided into multiple sub-pixels having different colors. Each sub-pixel is associated with a color, such as the primary colors red, green and blue or, in the alternative, may include non-primary colors such as white or yellow. Accordingly, color images may be displayed as a collection of pixels having different colors. The color of each individual pixel is controlled by the brightness of its sub-pixels.
Photo sensors are sensors that detect light. Upon receiving light, photo sensors generate signals in which its amplitude depends on the intensity of the light. By forming an array of photo sensors, one can detect images through a mapping of a signal generated by an individual photo sensor.
For a full color display, each pixel of an array of pixels incorporated into the display screen may include at least three sub-pixels. For example, red, green and blue (RGB) sub-pixels may form an RGB pixel. Equal amounts of light from each color can form white light.
There may be several different implementations in positioning a photo sensor proximal a sub-pixel or integrating a photo sensor with a sub-pixel. Typically, photo sensors are mapped to fewer than each pixel, for example, in a one-to-three ratio. A photo sensor is placed in a corner of a pixel partially covering the area of a sub-pixel, typically a red sub-pixel. The aperture ratio characterizes how much light from the pixel or sub-pixel can get through. An aperture ratio can be considered to be the portion of the pixel or sub-pixel that is available to emit light.
By covering a portion of one sub-pixel with a photo sensor element, the aperture ratio of the sub-pixel is reduced, and white light generated by the combination of light of the three sub-pixel RGB configuration is reduced. If the photo sensor reduces the aperture ratio of the red sub-pixel compared to the blue and green sub-pixels, the light from each of the colors do not mix in substantially equal amounts and the generation of white light can be inhibited. Therefore, the brightness of the display can be compromised by the placement of photo sensor elements integrated into one sub-pixel of plurality of pixels of an array of pixels.
Disclosed are input devices, electronic devices and methods for integrating photo sensors into sub-pixels of pixels of an array of pixels to substantially maintain the brightness of a touch screen display. In a full color display, each pixel of an array of pixels incorporated into the display screen can include at least three sub-pixels, for example three sub-pixels can form an RGB pixel. In one disclosed embodiment, one or more photo sensors are distributed across two colored sub-pixels. Accordingly, the aperture ratios of the sub-pixels can be more substantially equal than the aperture ratios of the sub-pixels when a single sub-pixel includes a photo sensor. In another disclosed embodiment, one or more photo sensors are distributed across three sub-pixels. Accordingly, the aperture ratios of the sub-pixels may be substantially equal so that the light from each of the colors may mix in better or substantially equal amounts to generate white light.
In another embodiment, a white sub-pixel may be included with the sub-pixels of a pixel. A photo sensor may be integrated into the white sub-pixel. In this manner, the three colors of the light of the sub-pixels can be combined to form white light that can be further brightened by the white light behind the photo sensor of the white sub-pixel.
The instant disclosure is provided to explain in an enabling fashion the best modes of making and using various embodiments in accordance with the present invention. The disclosure is further offered to enhance an understanding and appreciation for the invention principles and advantages thereof, rather than to limit in any manner the invention. While the preferred embodiments of the invention are illustrated and described here, it is clear that the invention is not so limited. Numerous modifications, changes, variations, substitutions, and equivalents will occur to those skilled in the art having the benefit of this disclosure without departing from the spirit and scope of the present invention as defined by the following claims. It is understood that the use of relational terms, if any, such as first and second, up and down, and the like are used solely to distinguish one from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions.
The electronic device 102 can be any type of wired or wireless device that includes a display screen 104. An electronic device that is a mobile communication device may be implemented as a cellular telephone (also called a mobile phone). The mobile communication device represents a wide variety of devices that have been developed for use within various networks. Such handheld communication devices include, for example, cellular telephones, messaging devices, personal digital assistants (PDAs), notebook or laptop computers incorporating communication modems, mobile data terminals, application specific gaming devices, video gaming devices incorporating wireless modems, and the like. Any of these portable devices may be referred to as a mobile station or user equipment. Herein, wireless communication technologies may include, for example, voice communication, the capability of transferring digital data, SMS messaging, Internet access, multi-media content access and/or voice over internet protocol (VoIP).
A user interface such as the display screen 104 that is an input device can be coupled to the controller 108. The display screen 104 may have a surface where in
The disclosed input devices, electronic devices and methods for integrating photo sensors into sub-pixels of pixels of an array of pixels may substantially maintain the brightness of a touch screen display. In one disclosed embodiment, one or more photo sensors are distributed across two colored sub-pixels. In another disclosed embodiment, one or more photo sensors are distributed across three sub-pixels. In yet another embodiment, a photo sensor may be integrated into a white sub-pixel. Accordingly, the aperture ratios of the sub-pixels may be substantially equal so that the light from each of the colors may mix in better or substantially equal amounts to generate white light.
This disclosure is intended to explain how to fashion and use various embodiments in accordance with the technology rather than to limit the true, intended, and fair scope and spirit thereof. The foregoing description is not intended to be exhaustive or to be limited to the precise forms disclosed. Modifications or variations are possible in light of the above teachings. The embodiment(s) was chosen and described to provide the best illustration of the principle of the described technology and its practical application, and to enable one of ordinary skill in the art to utilize the technology in various embodiments and with various modifications as are suited to the particular use contemplated. All such modifications and variations are within the scope of the invention as determined by the appended claims, as may be amended during the pendency of this application for patent, and all equivalents thereof, when interpreted in accordance with the breadth to which they are fairly, legally and equitably entitled.
