A touch screen with a screen surface, comprising: a housing; a plurality of infra-red light emitting diodes (LEDs) fastened to said housing; a first lens assembly arranged at a first edge of the touch screen for distributing light emitted by said LEDs in a plurality of directions, wherein a first section of the first lens assembly is aligned to direct a first portion of the light emitted by said LEDs along a plane substantially parallel to the screen surface, and wherein a second section of the first lens assembly is skewed at an angle with said screen surface to direct a second portion of the light emitted by said LEDs upward relative to said screen surface; a plurality of photodiode receivers fastened to said housing; a second lens assembly arranged at a second edge of the touch screen opposite the first edge, for receiving the first and second portions of light, wherein a first section of the second lens assembly is aligned to receive the first portion of the light and to further direct the first portion onto said photodiode receivers, and wherein a second section of the second lens assembly is skewed at an angle with said screen surface to receive reflections of the second portion of the light and to direct the reflections onto said photodiode receivers; an LED selector connected to said LEDs, for selectively activating said LEDs; a photodiode selector connected to said photodiode receivers, for selectively activating said photodiode receivers; a photodiode signal filter and amplifier connected to said photodiode receivers, for generating detection signals representing amounts of light detected on said photodiode receivers; and a processor fastened on said housing, for controlling said LED selector and said photodiode selector, and for processing the detection signals generated by said photodiode signal filter and amplifier to detect therefrom the proximity of an object to said screen surface, based on a measured intensity from at least one photodiode, wherein a default photodiode receiver intensity is the received intensity when no object is detected, wherein a first measured light intensity is below a default photodiode receiver intensity, when the object is touching the screen surface and blocking the first portions of the light, and a second measured light intensity is greater than the default photodiode receiver intensity, when the object is positioned above the screen surface and reflecting a portion of the second portion of the light. a housing; a plurality of infra-red light emitting diodes (LEDs) fastened to said housing; a first lens assembly arranged at a first edge of the touch screen for distributing light emitted by said LEDs in a plurality of directions, wherein a first section of the first lens assembly is aligned to direct a first portion of the light emitted by said LEDs along a plane substantially parallel to the screen surface, and wherein a second section of the first lens assembly is skewed at an angle with said screen surface to direct a second portion of the light emitted by said LEDs upward relative to said screen surface; a plurality of photodiode receivers fastened to said housing; a second lens assembly arranged at a second edge of the touch screen opposite the first edge, for receiving the first and second portions of light, wherein a first section of the second lens assembly is aligned to receive the first portion of the light and to further direct the first portion onto said photodiode receivers, and wherein a second section of the second lens assembly is skewed at an angle with said screen surface to receive reflections of the second portion of the light and to direct the reflections onto said photodiode receivers; an LED selector connected to said LEDs, for selectively activating said LEDs; a photodiode selector connected to said photodiode receivers, for selectively activating said photodiode receivers; a photodiode signal filter and amplifier connected to said photodiode receivers, for generating detection signals representing amounts of light detected on said photodiode receivers; and a processor fastened on said housing, for controlling said LED selector and said photodiode selector, and for processing the detection signals generated by said photodiode signal filter and amplifier to detect therefrom the proximity of an object to said screen surface, based on a measured intensity from at least one photodiode, wherein a default photodiode receiver intensity is the received intensity when no object is detected, wherein a first measured light intensity is below a default photodiode receiver intensity, when the object is touching the screen surface and blocking the first portions of the light, and a second measured light intensity is greater than the default photodiode receiver intensity, when the object is positioned above the screen surface and reflecting a portion of the second portion of the light.