Holographic object position and type sensing system and method

A method for determining the position and classification of an object, comprising the steps of:

• generating a pulsed light beam comprising an object beam;
• reflecting the object beam off an object whose position and classification are to be determined;
• illuminating a holographic template containing predetermined phase patterns corresponding to selected object types with an object beam reflected from the object, and wherein the reflected object beam interferes with the phase pattern present on the template, which convolves to produce a spot of light whose brightness is indicative of the degree of match between the interference pattern and the phase pattern on the template and whose location is indicative of the spatial location of the object;
• detecting the magnitude and location of the spot;
• generating signals indicative of the magnitude and location of the spot;
• processing the signals indicative of the magnitude and location of the spot to generate output signals indicative of the position of the object and classification of the object;
• and
• further processing the output signals to determine whether to enable or suppress active restraint measures.

A holographic object position and type sensing system for determining a presence and position of portion of an occupant in a vehicle seat comprising:

• a light source for outputting a pulsed light beam comprising an object beam;
• a holographic template comprising phase patterns for receiving an object beam that is reflected from an object, and wherein the reflected object beam interferes with the phase patterns present on the template, and convolution between the beam interference and the phase pattern produces a spot of light when there is an exact match, and wherein the brightness of the spot indicates the degree of match and the location of the spot indicates the spatial location of the object;
• a two-dimensional detector array for detecting the magnitude and location of the spot and for outputting signals indicative thereof;
• and
• a processor for processing the signals indicative of the magnitude and location of the spot to generate and output a signal indicative of the position of the object and a classification of the object, wherein at least one of the phase patterns of the template is indicative of the classification and spatial location of the occupant of a vehicle seat relative to an active restraint.

A holographic object position and type sensing system for determining a presence and position of portion of an occupant in a vehicle seat comprising:

• a light source for outputting a pulsed light beam comprising an object beam;
• a holographic template comprising phase patterns for receiving an object beam that is reflected from an object, and wherein the reflected object beam interferes with the phase patterns present on the template, and convolution between the beam interference and the phase pattern produces a spot of light when there is an exact match, and wherein the brightness of the spot indicates the degree of match and the location of the spot indicates the spatial location of the object;
• a two-dimensional detector array for detecting the magnitude and location of the spot and for outputting signals indicative thereof;
• and
• a processor for processing the signals indicative of the magnitude and location of the spot to generate and output a signal indicative of the position of the object and a classification of the object and determining, responsive to the output signal, whether to enable or suppress active restraint measures associated with the vehicle seat.