A projected capacitive touch sensing system comprising: a first transparent substrate below which a common plate electrode is positioned; an electromagnetic radiation source configured to emit electromagnetic radiation within a desired range of wavelengths, the electromagnetic radiation being coupled into the first substrate, such that at least a portion of the emitted electromagnetic radiation experiences total internal reflection within the first substrate and propagates down the first transparent substrate; a second transparent substrate on which patterned capacitive touch sensing electrodes are positioned that are spaced apart from the common plate electrode, are oriented in a plane parallel to the common plate electrode, and are positioned such that pairs of adjacent patterned capacitive touch sensing electrodes experience a capacitance therebetween, where the capacitance between a pair of adjacent patterned capacitive touch sensing electrodes changes based on changes in a distance between the first substrate on which the common plate electrode is positioned and the second substrate on which the pair of adjacent patterned capacitive touch sensing electrodes are positioned; a photo-capacitive or photo-conductive layer positioned on the patterned capacitive touch sensing electrodes; an air gap or a deformable, insulating or semi-insulating elastomer or fluid positioned between the common plate electrode and the patterned capacitive touch sensing electrodes; wherein the system is configured so that when sufficient pressure is applied to the first substrate to cause the first substrate to contact the photo-capacitive or photo-conductive layer, total internal reflection of the electromagnetic radiation in the first substrate is frustrated such that at least some of the electromagnetic radiation trapped within the first substrate escapes and is coupled into the photo-capacitive or photo-conductive layer to cause an increase in capacitance or conductance, electronic circuitry configured to sense a change in capacitance between the pair of adjacent patterned capacitive touch sensing electrodes and changes in capacitance or conductance of the photo-capacitive or photo-conductive layer, and to determine an input based on the sensed change in capacitance between the pair of adjacent patterned capacitive touch sensing electrodes and based on the increase in capacitance or conductance of the photo-capacitive or photo-conductive layer occurring when the first substrate contacts the photo-capacitive or photo-conductive layer. a first transparent substrate below which a common plate electrode is positioned; an electromagnetic radiation source configured to emit electromagnetic radiation within a desired range of wavelengths, the electromagnetic radiation being coupled into the first substrate, such that at least a portion of the emitted electromagnetic radiation experiences total internal reflection within the first substrate and propagates down the first transparent substrate; a second transparent substrate on which patterned capacitive touch sensing electrodes are positioned that are spaced apart from the common plate electrode, are oriented in a plane parallel to the common plate electrode, and are positioned such that pairs of adjacent patterned capacitive touch sensing electrodes experience a capacitance therebetween, where the capacitance between a pair of adjacent patterned capacitive touch sensing electrodes changes based on changes in a distance between the first substrate on which the common plate electrode is positioned and the second substrate on which the pair of adjacent patterned capacitive touch sensing electrodes are positioned; a photo-capacitive or photo-conductive layer positioned on the patterned capacitive touch sensing electrodes; an air gap or a deformable, insulating or semi-insulating elastomer or fluid positioned between the common plate electrode and the patterned capacitive touch sensing electrodes; wherein the system is configured so that when sufficient pressure is applied to the first substrate to cause the first substrate to contact the photo-capacitive or photo-conductive layer, total internal reflection of the electromagnetic radiation in the first substrate is frustrated such that at least some of the electromagnetic radiation trapped within the first substrate escapes and is coupled into the photo-capacitive or photo-conductive layer to cause an increase in capacitance or conductance, electronic circuitry configured to sense a change in capacitance between the pair of adjacent patterned capacitive touch sensing electrodes and changes in capacitance or conductance of the photo-capacitive or photo-conductive layer, and to determine an input based on the sensed change in capacitance between the pair of adjacent patterned capacitive touch sensing electrodes and based on the increase in capacitance or conductance of the photo-capacitive or photo-conductive layer occurring when the first substrate contacts the photo-capacitive or photo-conductive layer.