Claims
- 1. An image magnification control device for a camera comprising:
- distance detection means for detecting a distance "X.sub.0 " between a rear focal point of a photographic lens and an in-focus position from a delivery-amount of a focusing lens;
- defocus information detection means for detecting a defocus information "dx" of the photographic lens by using a light having passed through the photographic lens;
- focal length detection means for detecting a focal length "f.sub.0 " of the photographic lens;
- image magnification setting means for setting an image magnification "m.sub.0 " for taking a photograph;
- computation means for computing a control focal length "f.sub.1 " in accordance with an equation: ##EQU6## using said x.sub.0, d.sub.x, f.sub.0 and m.sub.0 ; and focal length control means for changing the focal length of the photographic lens so as to meet said control focal length, said focal length control means comprising motor drive means for driving and varying the focal length of the photographic lens.
- 2. An image magnification control device for a camera wherein either a single-shot photographing mode or a sequential-shot photographic mode can be selected, said device comprising:
- image magnification setting means for setting an image magnification to a certain magnification, said image magnification setting means comprising an image magnification input selector that allows a user to select among a plurality of magnifications; and
- control means for driving a photographic lens so as to maintain the image magnification set by said image magnification setting means,
- wherein said control means drives said photographic lens, in case the sequential-shot mode is selected, in such a fashion that once a subject is focused at the image magnification set by said image magnification setting means in the sequential-shot photographing mode, a focusing operation is sequentially performed at the set image magnification as a subject moves.
- 3. An image magnification control device for a camera wherein either a focus-priority mode or a shutter-release-priority mode can be selected, said device comprising:
- image magnification setting means for setting an image magnification to a certain magnification, said image magnification setting means comprising an image magnification input selector that allows a user to select among a plurality of magnifications; and
- control means for driving a photographic lens so as to maintain the image magnification set by said image magnification setting means,
- wherein said control means executes a focus-lock operation when a subject is focused in the focus-priority mode while the image magnification has not been set, and
- wherein said control means executes image magnification control without executing the focus-lock operation when a subject is focused in the focus-priority mode while the image magnification has been set by said image magnification setting means.
Priority Claims (6)
Number |
Date |
Country |
Kind |
63-237570 |
Sep 1988 |
JPX |
|
63-237571 |
Sep 1988 |
JPX |
|
63-237572 |
Sep 1988 |
JPX |
|
63-237573 |
Sep 1988 |
JPX |
|
63-237574 |
Sep 1988 |
JPX |
|
63-237575 |
Sep 1988 |
JPX |
|
Parent Case Info
This application is a continuation of application Ser. No. 07/652,038, filed Feb. 4, 1991, which is a continuation of 07/410,880, filed on Sep. 22, 1989, which issued as U.S. Pat. No.5,093,680 on Mar. 3, 1992.
US Referenced Citations (16)
Foreign Referenced Citations (29)
Number |
Date |
Country |
53-113527 |
Oct 1978 |
JPX |
54-25819 |
Feb 1979 |
JPX |
58-103273 |
Jun 1983 |
JPX |
59-64816 |
Apr 1984 |
JPX |
60-1602 |
Jan 1985 |
JPX |
61-26015 |
Feb 1986 |
JPX |
61-38917 |
Feb 1986 |
JPX |
61-230111 |
Oct 1986 |
JPX |
62-118328 |
May 1987 |
JPX |
62-133431 |
Jun 1987 |
JPX |
62-200340 |
Sep 1987 |
JPX |
63-5331 |
Jan 1988 |
JPX |
62-133430 |
Feb 1988 |
JPX |
63-131112 |
Jun 1988 |
JPX |
63-189817 |
Aug 1988 |
JPX |
63-220118 |
Sep 1988 |
JPX |
64-44428 |
Feb 1989 |
JPX |
64-44429 |
Feb 1989 |
JPX |
64-56406 |
Mar 1989 |
JPX |
64-62608 |
Mar 1989 |
JPX |
64-79713 |
Mar 1989 |
JPX |
1-99011 |
Apr 1989 |
JPX |
1-99012 |
Apr 1989 |
JPX |
1123206 |
May 1989 |
JPX |
1131509 |
May 1989 |
JPX |
1179113 |
Jul 1989 |
JPX |
1232311 |
Sep 1989 |
JPX |
1307711 |
Dec 1989 |
JPX |
2-12116 |
Jan 1990 |
JPX |
Non-Patent Literature Citations (4)
Entry |
P. 67 of Infinity Super Zoom 300 Camera Instruction Manual, published Jul. 1988. |
English Abstract of Japanese Patent No. 63-5331. |
English Abstract of Japanese Patent No. 64-62608. |
English Abstract of Japanese Patent No. 64-79713. |
Continuations (2)
|
Number |
Date |
Country |
Parent |
652038 |
Feb 1991 |
|
Parent |
410880 |
Sep 1989 |
|