Catalogue des appareils cinématographiques de la Cinémathèque française et du CNC

Type de l'appareil

tube n/b orthicon ; photocathode semi-transparente ; bobine de concentration ; déflecteur magnétique ; culot à 14 broches

Auteurs

Informations non disponibles

Fabricants

RCA - Radio Corporation of America
Camden, New Jersey

Utilisateurs

Informations non disponibles

Distributeurs

RCA - Radio Corporation of America
Camden, New Jersey

Sujet du modèle

Informations non disponibles

Objectif

Informations non disponibles

Taille de l'objet

Ouvert :
Informations non disponibles

Fermé :
Longueur : 38 cm
Largeur : 7.5 cm
Hauteur : 7.5 cm

Diamètre :
Informations non disponibles

Taille de la boîte de transport

Informations non disponibles

Remarques

Marque : "5820" ; "RCA Electron tube Made in USA".
"RCA-5820 is a television camera tube intended for both outdoor and studio pickup. It has exceptionally high sensitivity combined with a spectral responce approaching that of the eye. The 5820 is very stable in performance at all incident light levels on the object ranging from bright sunlight (several thousand foot-candles) to a deep shadow (one foot-candle or less). Commercially acceptable pictures can be obtained at incident light levels greater than about 10 foot-candles with appropriate setting of the camera lens strops. The photocathode utilized in the 5820 is characterized by a spectral response having high blue sensitivity, high green sensitivity, very good yellow sensitivity, good red sensitivity, and pratically no infrared sensitivity. This latter characteristic of the response prevents any color-masking by infrared, and thus permits gray-scale rendition of colors in nearly their true tonal gradation. [...] The 5820 has three sections : an image section, a scanning section, and a multiplier section. The image section contains a semi transparent photocathode on the inside of the faceplate, a grid to provide an electrostatic accelerating filed, and a target which consists of a thin glass disc with a fine mesh screen very closely spaced to it on the photocathode side. Focusing is accomplished by means of a magnetic field produced by an external coil, and by varying the photocathode voltage. [...] The opposite side of the glass is scanned by a low-velocity electron beam produced by the electron gun in the scanning section. This gun contains a thermionic cathode, a control grid and an accelerating grid. The beam is focused at the target by the magnetic field of an external focusing coil and the electrostatic field of grid. [...] The return screen is directed to the first dynode of a five-stage electrostatically focused multiplier. This utilizes the phenomenon of secondary emission to amplify signals composed of electron beams. The electrons in the beam impinging on the first dynode surface produce many other electrons, the number depending on the nergy of the impinging electrons. These secondary electrons are then directed to the second dynode and konck out more new electrons" (Notice RCA 5820 Image Orthicon for Outdoor and Studio Pickup Exceptional Sensitivity, Harrison, RCA, 1956).

Bibliographie

Notice RCA 5820 Image Orthicon for Outdoor and Studio Pickup Exceptional Sensitivity, Harrison, RCA, 1956.