System for determining a distance to an object

A system for determining a distance to an object comprising:

• a solid-state light source arranged for projecting a pattern of discrete spots of laser light towards said object in a sequence of pulses;
• a detector comprising a plurality of picture elements, said detector being configured for detecting light representing said pattern of discrete spots as reflected by said object in synchronization with said sequence of pulses;
• and
• processing means programmed to calculate said distance to said object as a function of exposure values generated by said picture elements in response to said detected light based on the amount of temporal overlap between the pulse emission window and the arrival of the reflected pulse by applying range gating to said sequence of pulses;
• wherein said picture elements are configured to generate said exposure values by accumulating, for all of the pulses of said sequence, a first amount of electrical charge representative of a first amount of light reflected by said object during a first predetermined time window overlapping with the pulse emission time window and a second electrical charge representative of a second amount of light reflected by said object during a second predetermined time window, said second predetermined time window occurring after said first predetermined time window;
• wherein each of said plurality of picture elements comprises at least two sets of charge storage wells, each set of charge storage wells being configured as a cascade so as to form a greater total charge storage capacity, said detecting of said first amount of light and said detecting of said second amount of light occurring at respective ones of said cascades.