Object Details
Manufacturer
Robert Cashman
Summary
This is one of a set artifacts that typify the infrared detectors those used by astronomers from the 1940's into the 1960's. This small glass tube is an infrared photocell manufactured in 1946 by Robert Cashman of Northwestern University. The tube is coated on part of the interior face with a very thin evaporated layer of lead sulfide (PbS). The conductivity of the coating is modified by impinging infrared photons. This change in conductivity, when amplified by appropriate electronic circuits, is a direct measure of the intensity of the infrared radiation. Detectors such as this were used for studies of the infrared spectra of stars by Cashman and his collaborator Gerard Kuiper. The set of detectors was donated to NASM in 1994 by Dale P. Cruikshank.
Credit Line
Gift of Dale P. Cruikshank
Inventory Number
A19940241001
Restrictions & Rights
Usage conditions apply
Type
INSTRUMENTS-Scientific
Materials
Glass
Steel
Lead Sulfide
Dimensions
3-D: 8.6 × 1.3 × 1.3cm (3 3/8 × 1/2 × 1/2 in.)
Storage: 13 × 10.2 × 1.9cm (5 1/8 × 4 × 3/4 in.)
Country of Origin
United States of America
See more items in
National Air and Space Museum Collection
Data Source
National Air and Space Museum
Link to Original Record
Record ID
nasm_A19940241001