| 摘要 |
1,252,100. Television. FERNSEH G.m.b.H. 5 May, 1970 [14 May, 1969], No. 21636/70. Heading H4F. In a colour television camera comprising pick-up tubes 12, 15, 17 e.g. of the type using photoconductive lead oxide, in conjunction with prisms 6-8 having green and blue reflective dichroic faces 10 and 13 respectively, additional uniform illumination of the tube faces to suppress afterglow is provided by directi ng light from a source 20 through a normal ground flat face 24 of prism 7 in a direction coincident with that part of the image light which has been reflected by the dichroic coating 10. The spectral composition of the additional light is controllable by displaceable filters 22, and the intensity of the source 20 is also controllable. A test image disposed in the additional light path may be focused in the photo-electric cathodes 11, 14 and 16 to verify the electronic and optical setting of the camera. |
