Model of Harries 'sunflower' projection cathode ray tube

Presentation model of Harries 'sunflower' projection cathode

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Presentation model of Harries 'sunflower' projection cathode
Science Museum Group
© The Board of Trustees of the Science Museum

Presentation model of Harries 'sunflower' projection cathode ray tube, made by 20th Century Electronics Ltd in 1970. The model was made for, and given to, Gilbert Tomes by his workforce at 20th Century Electronics (Later Centronic Ltd). During the late 1940s, 20th Century Electronics (Centronic in its earlier guise) made special radio valves for Owen Harries. Later, employees from 20th Century helped Harries develop this cathode ray tube from a patent Gilbert Tomes had placed in 1937. It used a system where an internal lens projected the picture from the rear of the fluorescent screen. An external lens could then be used to correct or enhance the picture. This tube was named the 'sunflower' tube as the optical configuration bore some resemblance to the flower. The tube was also a lot smaller than others made previously, meaning that TVs could be reduced in size and weight. Harries also believed that the sunflower tube was of utility in the development of colour TV: instead of using an expensive shadow mask tube, three sunflower tubes could be used instead, each with an appropriate colour filter.

Details

Category:
Nuclear Physics
Object Number:
2000-1515
Materials:
plastic (unidentified), stainless steel, steel (metal), glass and felt
Measurements:
overall: 75 mm x 152 mm x 87 mm, .28 kg
tube: 106 mm 34 mm,
type:
cathode ray tube
credit:
Gilbert Tomes