USA As Represented by Secretary of the Navy

US Government As Represented by the Secretary of the Army

Northrop Grumman Systems Corporation

The United States of America As Represented by the Dept of the Army

Conrad W Terrill

Donna J Advena

Vincent T Bly

Khoa V Dang

Stephen B Compana

The present invention is a modified darlington phototransistor wherein a phototransistor is coupled to a Bipolar Junction Transistor (BJT). This design provides a high sensitivity and a fast response and effectively increases the gain of the photocurrent. This circuit is particularly will suited for the readily available CMOS and Bipolar Complementary Metal Oxide Semiconductor (BiCMOS) processes prevalent today.

Visible imaging device using Darlington phototransistors

A device and method for detection of buried objects () utilizing a down looking infrared array () having infrared detectors () positioned in a sensor array (). This sensor array () may also contain ground penetrating radar () and EMI coils (). All signals from the ground penetrating radar (), EMI coils () and down looking infrared array () may be combined to generate alarms (). However, the down looking infrared array () may be utilized as a sole means of detecting buried objects (). This device and method for detecting buried objects () utilizing down looking infrared array () reduces the cost of construction and maintenance of such a device.

Device and method for the detection of buried objects

A fabrication technique for a test sample to characterize pyroelectric and erroelectric thin films for use in uncooled infrared focal plane arrays operated at a nominal 60 Hz. Most layers are patterned by a lift off technique, and those layers that are not lifted off are chemically etched or ion milled. The pyroelectric layer is thermally insulated from the substrate by a thick film layer of ZrO.sub.2. The pyroelectric layer is sandwiched between metal layers to form a capacitor. Direct measurement of the voltages between the capacitor plates, and of the temperature of these plates, results in a direct measurement of thin film temperature responsivity.

Test sample fabrication technique

Incident infrared radiation is focussed through a rotatable disk of germam onto a detector array. The disk has a thickness many times the wavelengths of the incident radiation and is partly covered with a pattern of germanium one-half wavelength of some preselected wavelength of the incident radiation. The pattern is a regular array of mesas, and acts as a phase grating which diffracts incident radiation. The diffracted (or blurred) image on the detector array is used as a reference level for background suppression.

Growing community of inventors

Lorton, VA, United States of America

Conrad W Terrill