Patent ID: 9621824
Date: 2017-04-11
CPC Classifications: G01J,H04N

Claim:
1. A thermal imager comprising: a detector, a lens, a shutter disposed between the detector and the lens, a motor operably connected to the shutter for moving the shutter between a first and a second position, the motor being a two-phase stepper motor, and a source of electrical energy operably connected to one or more of the detector, lens and motor by an electrical circuit, wherein the electrical circuit comprises one or more of a capacitor, a diode, and a resistor and the one or more of the capacitor, diode, and resistor reduce one or more of a capacitance, voltage, and inductance of the electrical energy in the electrical circuit to below a nonincendiary level required for intrinsic safety, and wherein the two-phase stepper motor comprises at least two coils, each coil having a first and a second end and wherein the electrical circuit comprises four resistors, one resistor in electrical communication with each of the first and second ends of each of the at least two coils.