Optical temperature indicator using thermochromic semiconductors

DETAILED DESCRIPTION According to its major aspects this invention is a composition to indicate temperature by utilizing thermochromic semiconductor material.
Another object of the invention is to place the thermochromic semiconductor material within an enamel or glass matrix to allow reversible indications of high temperatures without destroying the semiconductor material.
Another object of the invention is to use the various color changes of the thermochromic semiconductor material to provide a multi-level response to indicate the various levels of temperature.
Another object of the invention is to mount the temperature indicator directly upon a range top eye or other surface which requires a temperature indication.
Another object of the invention is to utilize the thermochromic semiconductor with a proper background to form a sign which is viewable only at or above a predetermined dangerous temperature.
A further preferred object of the invention is to utilize cadmium sulfide as the thermochromic temperature indicator material.
Other features and advantages of the present invention will be apparent to those skilled in the art from a careful reading of the Detailed Description of a Preferred Embodiment presented below and accompanied by the drawings.