Rear view vision device

• US 3,947,095 A
• Filed: 03/18/1974
• Issued: 03/30/1976
• Est. Priority Date: 03/18/1974
• Status: Expired due to Term

• Current Assignee: Marie Saratore
• Original Assignee: Marie Saratore
• Inventors: Moultrie, Charles W.
• Primary Examiner(s): Corbin, John K.
• Assistant Examiner(s): Evans, F. L.
• Application Number:
  US05/452,061
• Time in Patent Office: 743 Days
• Field of Search: 350/52, 350/211, 350/301, 350/302, 350/307
• US Class Current: 359/505
• CPC Class Codes: B60R 1/10 Front-view mirror arrangements; specially adapted for covering the peripheral part of the vehicle B60R1/002; Periscope arrangements , i.e. optical devices using combinations of mirrors, lenses, prisms or the like specially adapted for covering the peripheral part of the vehicle B60R1/002; for viewing traffic-lights B60R1/005; Other mirror arrangements giving a view from above or under the vehicle
• CPC Class Codes: G02B 17/02 Catoptric systems, e.g. image erecting and reversing system

Abstract

Compact periscopic device particularly adapted for vehicular rear vision, including an optical train to provide a wide field of view with optimum resolution and brightness and adapted to the confines of a relatively small housing enclosure. The optical train directs the incoming light rays through a series of direction reversals whereby the housing size requirements are considerably reduced. Further, the optical train consists of a pair of alternately operable, Fresnel-type objective lenses of differing focal length to provide for either a wide unit magnification of rear-viewed objects in one instance or a greatly expanded field of view in another instance. The optical train also includes image-reversing and image-inversion reflective surfaces, to correct for lens reversal and inversion of the image.

Claims

1. A compact periscopic device for vehicular rear vision comprising:

a housing mounted in a vehicle roof with an image receiving opening therein directed rearwardly and extending above the roof, and having an image viewing opening therein directed generally downward inside the vehicle;

a transparent seal extending over said image receiving opening;

an angularly movable objective lens having a selected focal length angularly movable into and out of the path of light through said image receiving opening;

a screen adapted to accommodate an image to be focused thereon by said lens and positioned in said housing for viewing through said image viewing opening;

a second objective lens having a different focal length than the focal length of said first lens and angularly movable into and out of the path of light alternately of said first lens and adapted to focus an image on said screen as said first lens is out of position to focus an image on said screen;

a plurality of image reflecting surfaces positioned in said housing and adapted to direct the image along a path through a series of direction changing reversals between said image receiving opening and said image viewing opening and including means to correct for optical reversal and means to correct for optical inversion of the image, comprising a pair of image reversing mirrors disposed in angular relation with respect to each other and generally facing each other and converging to an apex in the image path of said transparent seal, and a mirror spaced beneath and downstream of the image path reflected by said mirrors to correct for optical inversion, said screen being in the path of said image through said image reversing mirrors, and said image inversion mirror, said image inversion mirror being downstream of said screen and directing the image through said image viewing opening;

one of said objective lenses being upstream of said image reversing mirrors and the other of said objective lenses being downstream of said image reversing mirrors and means selectively moving said lenses into and out of the path of light through said image receiving opening alternately of each other.

2. The periscopic device of claim 1, wherein said first objective lens has a focal length adapted to focus a generally full-size image on said screen and said second objective lens has a focal length adapted to focus an expanded wide field image on said screen, and link and lever means pivotally connected with said lenses for alternately and selectively moving one lens into position to focus an image on said screen and moving the lens not in position to focus an image on the screen out of the path of light through the image receiving opening.

3. The periscopic device of claim 1, wherein said first mentioned objective lens comprises a horizontally elongated unit magnification standard lens and said second mentioned objective lens comprises a horizontally elongated wide angle reduced image size lens, wherein said lenses are transversely pivoted to said housing and a single lever is effective to move one of said lenses into the path of light through the image receiving opening and the other of said lenses out of the path of light through the image receiving opening.

4. The periscopic device of claim 3, wherein the pair of mirrors in angular relation with respect to each other and converging to an apex to correct for optical reversal, is positioned between said pair of lenses and disposed at equal angles relative to each of said lenses in their respective image focusing positions.

5. The periscopic device of claim 4, wherein said equal angles relative to each of said lenses is in the order of 15°

to 30°

.

6. The periscopic device of claim 4, wherein said pair of lenses are Fresnel-type lenses and are operably interconnected by a control linkage to accommodate alternate and selective positioning of one of said pair of lenses in a focusing position, while the other of said pair of lenses is positioned in an out-of-the-way, inoperative position.

7. The periscopic device of claim 6, wherein the screen comprises a Fresnel-type image forming screen.

8. The periscopic device of claim 7, including a light shield framing an edge of said unit magnification standard lens when in an operable image focusing position, and wherein said control linkage is operable to position said light shield coincidental with positioning said unit magnification standard lens in an operable image focusing position.

9. A compact periscopic device for vehicular rear vision requiring a minimum amount of vertical space comprising:

a housing mounted in a vehicle roof with an image receiving opening therein, rearwardly directed and extending above the roof, and having an image viewing opening therein directed downwardly inside the vehicle;

a screen between said openings having a focusing surface thereon;

a pair of objective lenses within said housing, including a first lens of one focal length supported in said housing for selective angular movement about a fixed axis between an operable and non-operable position, and a second objective lens of a different focal length than said first lens also supported in said housing for selective angular movement about a fixed axis spaced from the axis of angular movement of said first objective lens and movable between an operable and non-operable position alternately of the position of said first lens, whereby either lens may optionally be brought into position to focus an image on said screen;

spaced partitions between said openings to retard light scattering;

a plurality of image reflecting surfaces supported in said housing on opposite sides of said partitions and adapted to direct the image along a path between said image receiving opening and said image viewing opening and through one of said lenses when positioned downstream of said image reflecting surfaces, and including a pair of facing right-angled mirrors converging to an apex at the image path to correct for optical reversal and a second mirror in the image path to correct for optical inversion of the image;

said lenses being movable about spaced transverse axes and extending along at least one of said partitions when in a non-operable position, on opposite sides of said at least one partition.

10. The compact periscopic device of claim 9, wherein said pair of lenses comprise comparatively thin horizontally elongated Fresnel-type lenses including a unit magnification standard lens and a spaced wide angle reduced image size lens.

11. The periscopic device of claim 10 including a control linkage operably interconnecting said pair of objective lenses and a single lever for operating said control linkage to alternately and selectively position one of said pair of objective lenses in a focusing position and to position the other of said pair of lenses in an out-of-the-way, inoperative position along the at least one of said partitions.

12. The compact periscopic device of claim 11, wherein the first and second objective lenses are elongated Fresnel lenses and the screen is downstream of both lenses and comprises a horizontally elongated Fresnel-type image forming screen.