The Image Orthicon tube was developed at RCA by Albert Rose, Paul K. Weimer, and Harold B. Law. They presented a paper "The Image Orthicon - a sensitive television pickup tube" at the Winter Technical Meeting of the I.R.E. in New York on January 24, 1946.

This tube and it's derivatives, sensitive and flexible in operation proved to be a popular choice for television cameras from 1946 until well into the 1970s.

 

The Image Orthicon tube was quite large and and had many controls that needed adjustment. This meant that the cameras were also large and complex, especially the colour cameras that used three tubes! All these problems were overcome and by the late 1950s cameras were stable and reliable in use.

 

One of the operational problems was if the camera was left looking at a stationary image for a length of time that image would "stick" and take some time to disappear. As the tube aged this effect got worse. Camera manufacturers introduced a device, the image orbiter, this slowly moved the total scanning of the tube around in a circular motion so the picture was never stationary. This was normally switched off for transmission.

 

In 1964 EEV announced a new target material called Elcon (from ELectronic CONduction) This virtually eliminated this sticking problem and tube performance was maintained for much longer. The camera was slightly simpliyfied as the image orbitor was no longer needed.

 

Index
4.5 Inch Image Orthicon Tubes:-
Page 01EMI tube type 9565
Page 02 Cut-a-way view
Page 03Front view
Page 04 Pye Scanning Yoke 1
Page 05Pye Scanning Yoke 2
Page 06Pye Scanning Yoke 3
Page 07Marconi Scanning Yoke 1
Page 08Marconi Scanning Yoke 2
Page 09Transit case for Image Orthicon Tubes
3 Inch Image Orthicon Tubes:-
Page 10EEV 3 Inch Image Orthicon tube
Page 11Emitron 3 Inch Image Orthicon tube
Page 12RCA 3 Inch Image Orthicon tube
Page 13RCA 3 Inch Image Orthicon tube, development type label.
Page 14Image Orthicon Dynode Structure
Page 15Marconi Scanning yoke 3
Page 163 inch Image Orthicon tube voltages diagram
Page 17RCA type 5820 3 inch Image Orthicon tube and scanning yoke
Page 18Transit case for Image Orthicon tubes
Page 19Spare page
Other Image Orthicon Tubes:-
Page 20 Hitachi 2 Inch Image Orthicon tube
Page 21 Hitachi transit case for 2 inch Image Orthicon tube
Page 22 Spare page
Page 23 RCA "Mimo" midget Image Orthicon tube, picture
Page 24 RCA "Mimo" midget Image Orthicon tube, cross sectional diagram
page 25 Spare page
Page 26 Image Isocon tube #1
Page 27Image isocon tube #2

Data Sheets:-
EEV 7295C (P811/E) 4.5 inch Image Orthicon
EEV 7389C (P822 ) 4.5 inch Image Orthicon
EEV P874 3 inch Image Orthicon
EEV P875 3 inch Image Orthicon
RCA 5820 3 inch Image Orthicon (1956)
RCA 7513 3 inch Image Orthicon (1966)
RCA 2P21 3 inch Image Orthicon tube (1949)
RCA 2P22 Mimo 1-3/32 inch Image Orthicon tube (1946)
RCA 2P23 3 inch Image Orthicon tube (1949)

Data booklets:-

EMI 4.5 inch tube brochure
English Electric,  Image Orthicon 4.5 inch guidance booklet
English Electric,  Image Orthicon paper presented at Montreux 1965

Image Orthicon,  Simple description
Image Orthicon,  Warranty documents
Typical Operating Conditions for 4.5 inch Image Orthicon
EMI note                Guide to "Sticking" times

Reading List:-
The Image Orthicon - a sensitive television pickup tube, RCA Television Review Vol IV. 1942-46

Television Camera Tubes, Wireless World, May 1950, p162-5
New Television Camera Tube, (4.5inch) Wireless World, May 1954, p225
BBC Image Orthicon line up instructions for Pye Mk3 camera

Elcon Target Announcement, Dec 1964
Image Isocon, from Royal Television Society journal vol.11 no.11 1967
RCA Mimo miniature Image Orthicon, from RCA review September 1946

 

Adverts:-
EEV Period advert 1957
EEV Period advert 1965