A spherical coordinate sensor comprising: a circuit board; at least one light emitter mounted on said circuit board, each light emitter operable when activated to project light across a detection zone; a focusing optical part mounted on said circuit board and receiving light from the detection zone, comprising: a dome shaped top with a cavity carved out of the center of the dome, the interior of the dome being a concave mirror, wherein the bottom of the cavity is a light-transmissive input surface through which light enters the focusing optical part; a convex mirror opposite the input surface, wherein said concave mirror and the convex mirror are a reflective objective, wherein the light is reflected and focused inside the focusing optical part; and a concave exit surface through which focused light exits the focusing optical part, said convex mirror being at the top of the exit surface; a camera comprising a plurality of pixel sensors, mounted on said circuit board beneath said focusing optical part such that when the received light enters said focusing optical part at a three-dimensional angle of incidence, comprising a polar angle and an azimuth angle, denoted ( θ i, φ j), more light arrives at a respective camera pixel sensor than at any of the other camera pixel sensors; and a processor connected to said at least one light emitter and to said camera, the processor being configured to determine a polar angle, θ, and an azimuth angle, φ, of a reflective object within the detection zone relative to said focusing optical part, based on the camera pixel sensor that detects the greatest amount of the object's reflection. a circuit board; at least one light emitter mounted on said circuit board, each light emitter operable when activated to project light across a detection zone; a focusing optical part mounted on said circuit board and receiving light from the detection zone, comprising: a dome shaped top with a cavity carved out of the center of the dome, the interior of the dome being a concave mirror, wherein the bottom of the cavity is a light-transmissive input surface through which light enters the focusing optical part; a convex mirror opposite the input surface, wherein said concave mirror and the convex mirror are a reflective objective, wherein the light is reflected and focused inside the focusing optical part; and a concave exit surface through which focused light exits the focusing optical part, said convex mirror being at the top of the exit surface; a dome shaped top with a cavity carved out of the center of the dome, the interior of the dome being a concave mirror, wherein the bottom of the cavity is a light-transmissive input surface through which light enters the focusing optical part; a convex mirror opposite the input surface, wherein said concave mirror and the convex mirror are a reflective objective, wherein the light is reflected and focused inside the focusing optical part; and a concave exit surface through which focused light exits the focusing optical part, said convex mirror being at the top of the exit surface; a camera comprising a plurality of pixel sensors, mounted on said circuit board beneath said focusing optical part such that when the received light enters said focusing optical part at a three-dimensional angle of incidence, comprising a polar angle and an azimuth angle, denoted ( θ i, φ j), more light arrives at a respective camera pixel sensor than at any of the other camera pixel sensors; and a processor connected to said at least one light emitter and to said camera, the processor being configured to determine a polar angle, θ, and an azimuth angle, φ, of a reflective object within the detection zone relative to said focusing optical part, based on the camera pixel sensor that detects the greatest amount of the object's reflection.