Object discriminator

An apparatus for detecting selected objects, comprising in combination:

• video camera means having an image path for receiving reflected light from objects at which the video camera means is pointed, a video signal processor for providing electrical signals corresponding to the objects viewed, and a monitor which receives the electrical signals for electronically displaying the image;
• a polarizer mounted to the video camera means in the image path for rotation about an axis of rotation;
• rotational means for rotating the polarizer about the axis of rotation to produce alternating contrasts in intensity of the light being polarized;
• and
• frequency filter means located between the video signal processor and the monitor for filtering electrical signals produced by the video signal processor below a selected frequency, the selected frequency being in the range from 100 KHZ to two MHZ.

A method for searching for selected objects, comprising:

• providing a video camera having an image path for receiving reflected light from objects at which the video camera is pointed;
• providing a polarizer;
• mounting the polarizer in alignment with the image path;
• passing light reflected from the objects through the polarizer and determining if any of the light will horizontally polarize, creating a first image, and if any of the light will vertically polarize, creating a second image, and rapidly alternating the first and second images so as to create alternating contrasts in intensity of the light being polarized;
• providing electrical signals from the video camera means in response to the objects viewed;
• and
• filtering the electrical signals produced by the video camera below a selected frequency which is selected to substantially reduce the display of background objects viewed which reflect light that does not differ when passing through the rotating polarizer, and passing electrical signals produced by the video camera above the selected frequency.

A method for searching for selected objects, comprising:

• providing a video camera having an image path for receiving reflected light from objects at which the video camera is pointed, a video signal processor for providing electrical signals in response to the objects viewed, and a monitor for displaying the object in response to the electrical signals received from the video signal processor;
• providing a polarizer;
• mounting the polarizer about an axis of rotation in alignment with the image path;
• rotating the polarizer about the axis of rotation, providing alternating contrasts in intensity of the light being polarized;
• providing electrical signals from the video signal processor in response to the objects viewed;
• and
• filtering the electrical signals produced by the video signal processor below a selected frequency which selected to be in the range from 100 KHZ to two MHZ.