Patent ID: 7091874

Claim:
A temperature compensated warning lamp apparatus for use with an electrical power source and comprising: (a) an electrical illumination element illuminated by an activation signal at a photometric level related to a selected electrical parameter of said activation signal; (b) a temperature sensor thermally engaged with said illumination element and cooperating with said illumination element and an electrical power source to vary said selected electrical parameter of said activation signal in relation to an element temperature of said element sensed by said sensor to thereby control said photometric level of said element in relation to said element temperature; (c) an illumination controller coupled to said illumination element and having said temperature sensor coupled thereto; (d) said controller generating said activation signal as a pulse width modulated activation signal of which a pulse width can be varied to thereby vary said photometric level of said illumination element; and (e) said controller cooperating with said temperature sensor to vary said pulse width of said activation signal in relation to said element temperature.