GB1395588A - Mechanism for relative adjustment of axially-spaced lens components of an optical system - Google Patents

Abstract

1395588 Zoom lenses H MITO 23 Oct 1972 [10 Nov 1971] 48802/72 Heading G2J An optical system comprising a focusing component 1, 5 and a zooming component 2, 6, both axially moveable, has an operating member 23 so coupled to both components that axial movement of the member 23 moves one of the components, e.g. 2,6 and rotary movement of the member 23 around the axis moves the other 1,5. The member 23 has a guide member 26 which engages an axial slot 31 in a focusing ring 30, so that rotation of the member 23 moves the parts 1, 5, 30 axially by the helicoid mechanism 33, 35. Guide members 22, likewise mounted on the member 23, engage an annular slot 21 in a slidable ring 20 which carries a pin 29 which engages a slot 19 in a cylinder 14, whereby axial movement of the member 23 and hence of ring 20 rotates the cylinder 14 inside the ring 20 and causes pins 17, 18 which engage slots 15, 16 in the cylinder 14 to move axially and take with them the component 2, 6 and a compensating lens component 3, 7. Slots (12) 13 in the fixed portion 11 of the system accomodate axial movement of the pins 17, 18, 29. In a second embodiment, Figs. 3, 4 (not shown), the ring 20 is dispensed with, and a guide member (122) engages an annular slot (121) in the cylinder (114). Focusing is performed as in Fig. 1, but zooming is carried out by axially moving the member (123), which causes the cylinder (114) to move axially and the zooming and compensating components (102, 106, 107) to rotate and move axially due to the engagement of pins (117, 118) on the components with slots (115, 139) and (116, 140) in the parts (114, 111). In a third embodiment, Fig. 5, in which the member 23 is not shown zooming is performed by axially moving a ring 220 which is connected by strips 243, 244 passing over pulleys 245, 246 on the fixed part 211 to a rotatable cylinder 214, e.g. at 249. Pins 217, 218 on the zooming and compensating components 206, 207 engage in slots 215, 216 in the cylinder 214, axial movement of the pins being accommodated by a slot 212 in the part 211. Rotation of the ring 220 is prevented by a pin 213 which engages a hole 229 in the ring. Focusing is by rotation of the member corresponding to 23, as in Fig. 1.