A touch sensing apparatus is provided comprising: a light transmissive panel that defines a touch surface, a plurality of light emitters and detectors arranged along a perimeter of the light transmissive panel, a plurality of optical components arranged along the perimeter of the light transmissive panel, wherein the light emitters are arranged to emit a respective beam of emitted light and the optical components are configured to direct the emitted light to a path across the light transmissive panel. Optionally, optical components comprise a light guide arranged to receive light from the light emitters through a first surface and couple out light travelling in the light guide to the touch surface through a second surface. The second surface may be diffusively transmissive. The light guide may further comprise a reflective surface configured to internally reflect light travelling in the light guide from the first surface to the diffusive surface. The reflective surface may be diffusely reflective, partially diffusely reflective, or specularly reflective.

A unit pixel arranged along with a display pixel in each pixel of a display panel is provided. The unit pixel may include a thin-film transistor (TFT) photodetector including an active layer formed of amorphous silicon or polycrystalline silicon on an amorphous transparent substrate, and at least one transistor electrically coupled to the TFT photodetector and configured to generate a voltage output from photocurrent generated from the active layer.

An electronic device is provided which includes a light emitting module that radiates infrared light, a window disposed on the light emitting module and having a specific refractive index with respect to the infrared light, wherein the window includes a refraction part that totally reflects the infrared light inside the window in correspondence with the specific refractive index, and a fingerprint sensor disposed under the window and obtaining a fingerprint of a user based on a user input on the window by using scattered light of the infrared light.

An input device may include an image sensor having an imaging surface that includes an array of pixels, and an optical waveguide layer carried by the imaging surface and having an exposed user surface and a first refractive index associated therewith. The input device may also include a substrate between the optical waveguide layer and the image sensor and having a second refractive index associated therewith that is lower than first refractive index. A collimation layer may be between the image sensor and the substrate. A light source may be configured to transmit light into the optical waveguide so that the light therein undergoes a total internal reflection. The optical waveguide may be adjacent the imaging surface so that an object brought into contact with the exposed user surface disturbs the total internal reflection resulting in an image pattern on the imaging surface.

A touch screen panel using a thin film transistor (TFT) photodetector includes a touch panel including a plurality of unit patterns for sensing light reflected by a touch by using a TFT photodetector including an active layer formed of amorphous silicon or polycrystalline silicon on an amorphous transparent material, and a controller configured to scan the plurality of unit patterns and read touch coordinates as a result of the scanning.

A touch screen in the form of a panel is capable of conducting signals and a tomograph including signal flow ports is positioned adjacent the panel with the signal flow ports arrayed around the border of the panel at discrete locations. Signals are introduced into the panel to pass from each discrete border location to a plurality of other discrete border locations for being detected and tomographically processed to determine if any change occurred to signals due to the panel being touched during signal passage through the panel, and therefrom determine any local area on the panel where a change occurred. The tomograph computes and outputs a signal indicative of a panel touch and location, which can be shown on a display.

An optical touch-sensitive device is able to determine the locations of multiple simultaneous touch events. The optical touch-sensitive device includes multiple emitters and detectors coupled with an optical coupler assembly through a waveguide on the surface on the optical-touch sensitive device. Each emitter produces optical beams which propagate in the waveguide via total internal reflection and are received by the detectors. Touch events disturb the optical beams, and are determined based on the disturbances. The waveguide has at least one dead zone on its surface. The dead zone is formed with a cover layer having a top surface and a bottom surface where the bottom surface of the cover layer is directly coupled to the top surface of the waveguide. The cover layer preserves optical beam propagation in the waveguide and makes the dead zone insensitive to touches on the top surface of the cover layer.

The invention relates to a device for detecting electromagnetic radiation, said device comprising at least one row of photoresistors (45), each photoresistor comprising an active portion comprising organic semiconductor materials.

A touch system is described having a method of determining touch of one or more objects on a touch surface of a touch-sensitive apparatus, wherein the method operates in a time sequence of frames, each frame comprising the steps of: for a current frame, processing an output signal of the touch sensitive apparatus to generate one or more touch traces, each touch trace having one or more characteristics; and outputting a confirmed touch signal for each touch trace having a touch trace matching at least one of said one or more characteristics in a first number of frames preceding the current frame, wherein the first number of frames is determined in dependence on said one or more characteristics.

A touch-sensing display panel, comprising an LCD unit including a backlight and a plurality of image-forming pixel elements arranged in a central region. A planar light guide with a first refractive index has a front surface forming a touch-sensing region and an opposite rear surface facing the LCD unit. A plurality of light emitters are emulated by passing light from the backlight through pixel elements of first selected portions of a peripheral region of the LCD unit into the light guide for propagation therein through total internal reflection, and a plurality of light detectors are connected to receive light from the light guide.