Sigma Research — 6 Patents, Ranked #87,099

Patents per Year

Showing 1–4 of 4 inventors

Patent	Est. Value	Year
Direct expansion solar collector-heat pump system	$190K	1983
Ultrasonic method and apparatus for determining the depth of a crack in a solid material	$82K	1985
Flaw imaging in ferrous and nonferrous materials using magneto-optic visualization	$68K	1986