Kunz Photoelectric cells

Title

Kunz Photoelectric cells

Subject

Astronomy
photometry

Description

The photocell is hand blown glass or quartz. Within in the cell is an alkali metal (lithium, sodium, or potassium) that covers the inside and is a cathode emitting electrons when illuminated. A well insulated wire forming a ring centered in the bulb acts as an anode for collecting the emitted electrons. The inside of the bulb is filled with an inert gas such as helium, neon or argon.

The cell with number 15 (Wisconsin inventory number) bear Stebbins’ number 54. It is a typical glass tube in almost original condition.

The second cell is number 23 in Wisconsin’s inventory and bears Stebbins’ number QK 37-4 indicating it is a quartz tube with potassium hydride as the photo-cathode material. It was produced in 1937. This tube comes in an original cardboard box labeled with QK-37-1 and QK37-4. The box is also historically significant.

Creator

Jakob Kunz, University of Illinois Department of Physics
Observatory

Publisher

On loan from the University of Wisconsin Department of Astronomy.

Date

1915 and 1937

Language

Englsih

Type

physical object

Coverage

University of Illinois Observatory, Urbana, Il

Files

IMG_5798.JPG
IMG_5799.JPG

Collection

Citation

Jakob Kunz, University of Illinois Department of Physics Observatory , “Kunz Photoelectric cells,” University of Illinois Observatory Collection, accessed May 20, 2018, http://uiobservatory.omeka.net/items/show/71.