GB1298853A - Apparatus for monitoring a remote scene in both sound and vision - Google Patents

Abstract

1298853 Television INDUSTRIE A ZANUSSI SpA 4 March 1970 [7 March 1969 8 Aug 1969] 10522/70 Heading H4F [Also in Division E2] A unit for enabling a flat occupier &c. to observe and hear a caller before allowing him to enter, comprises, in a box 3, Figs. 1, 2 mounted in the entrance hall wall 25 &c., an upwardly directed television camera 2 having its direction of view made horizontal by mirror 11 and an intercom system 1. The vertical positioning of camera 2 in its own compartment renders the unit thinner and less subject to theft of the camera. Various burglar protective systems are used. The partition 9 may have many holes 10 therein only one of which however overlies the camera lens, thereby making it more difficult for a prospective damager to find the lens. Alternately only one hole 10 may be provided, Fig. 4 (not shown) this being normally covered by a shutter which is only removed under the control of the occupier when the caller announces his presence. The glass in viewing window 8 may carry an electrical conductor 12, Fig. 3, which, when broken on breaking of the window, de-energizes a relay 22. This closes contact 23, which energizes solenoid 24. The solenoid plunger 21 is retracted and allows a heavy shutter 13 to fall over the broken window. For viewing in dark &c. conditions, fluorescent strip lighting may be provided externally (18), Fig. 1 or internally (28), Fig. 4, of the box. The heat fromlight (28) helps to demist the window 8 and a block of silica gel 15 also reduces the humidity of the box. The light (28) is normally fed with a reduced voltage, but this is changed to full voltage by the occupier, together with the opening of shutter (26) on the caller announcing his presence.