Patent ID: 7623221

Claim:
Apparatus for determining distance comprising: a transmitting unit for emitting a light pulse of a predetermined pulse duration beginning with a leading rising edge and ending with a trailing falling edge, wherein the transmitting unit has a first control input and is adapted to emit a light pulse when a transmission start signal is applied to the first control input, a receiver matrix having at least one photoelectric element, wherein the receiver matrix has a measurement output for an output signal and is adapted to output an output signal which is derived from a measurement signal produced by the photoelectric element in dependence on light incident on the photoelectric element, and a control unit which is connected to the transmitting unit and the receiver matrix and adapted to produce the transmission start signal and output it to the transmitting unit and to receive the output signal from the receiver matrix and evaluate it, characterized in that the receiver matrix has a second control input for an integrator control signal and a first and a second integrator which are connected to a single photoelectric element and the second control input, are activatable by the integrator control signal independently of each other and are respectively adapted to integrate the measurement signal over an integration time predetermined by the integrator control signal and thereby to form a respective integrator state and to output the integrator states as an output signal, wherein the control unit is adapted to: carry out a measurement cycle with a first activity period of time by delivering two respective integrator control signals firstly to activate the first integrator for a first integration time corresponding to the first activity period of time and after a first elapse of the first activity period of time to deactivate the first integrator and activate the second integrator, execute a second measurement cycle with a second activity period of time after the execution of a first measurement cycle with a first activity period of time, and when executing the second measurement cycle the control unit is adapted to allow a waiting period of time to elapse after the delivery of the transmission start signal and to deliver the integrator control signal for starting the first integrator after the elapse of the waiting period of time, wherein the control unit is adapted to determine a distance of a region-of-interest in relation to the receiver matrix on the basis of the output signal of the receiver matrix of the first measurement cycle and to make the waiting period of time less than or equal to a transit time of light over a path corresponding to double the distance, and form a distance signal on the basis of the emission of a light pulse and evaluation of the integrator states, to be associated therewith, of the integrators.