JPH0293416A - Camera - Google Patents

Abstract

PURPOSE:To automatically move a zoom lens to a zoom edge by positioning a photographing lens in a location corresponding to a conversion lens in response to a signal at the time of mounting the conversion lens. CONSTITUTION:When a conversion lens frame is mounted, the signal discriminating wide or telescopic one according to a pushing amount from a detecting switch 15 is outputted and inputted to a control means 32. The output of a focal length (zoom value) detecting means 33 is inputted to the control means 32. When a wide conversion lens mounting signal is inputted from the detecting switch 15, the zoom lens in a photographing lens unit 35 is driven to a wide edge through a driving circuit 34 by the wide control signal of the control circuit 32. In the same way, when a telescopic lens signal is inputted, the zoom lens moves to the longest focus pide. Therefore, when the conversion lens is mounted, a desirable photographing condition is automatically attained.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a camera, and more particularly to a camera that can be equipped with a conversion lens.

[Prior Art] In a compact zoom camera, the range in which the focal length changes due to zooming is relatively narrow, so a conversion lens is often attached to the camera in order to expand the range in which the focal length changes. In other words, for example, when a wide conversion lens is attached to a camera, the focal length can be made shorter than when the same lens is not attached, and when a teleconversion lens is attached, the focal length can be made shorter than when the same lens is not attached. The focal length can be made longer in comparison.

[Problem to be Solved by the Invention] By the way, the purpose of using a conversion lens in this way is to obtain a focal length that cannot be obtained when the conversion lens is not attached, and for this purpose, the zoom lens is generally set at the zoom end. The conversion lens is used in this condition. In other words, when using a width conversion lens or a telephoto conversion lens, it is required to move the zoom lens to the wide end or telephoto end, but it is troublesome for the user to recognize this and switch the zoom state each time. This is not preferable because it may also cause erroneous recognition.

In view of these points, an object of the present invention is to provide a camera in which a conversion lens is automatically moved to the zoom end or the like when the conversion lens is attached.

[Means and effects for solving the problem] The camera of the present invention uses a detection means to detect that a conversion lens is attached, and responds to the output of this detection means to change the focal length of the photographic lens when using the conversion lens. The lens position is adjusted to the corresponding predetermined position.

[Example Figure 2 shows a compact zoom camera to which the present invention is applied.
A state in which the conversion lens frame shown in FIGS. 4(A) and 4(B) is attached is shown. FIGS. 3A and 3B show the conversion lens frame removed.

As shown in FIGS. 3(A) and 3(B), there are two distance-measuring light receiving windows 3 above the photographic lens 2 at approximately the middle position of the front surface of the camera body 1 of this compact zoom camera.
4 are provided. A rectangular area around the photographic lens 2 protrudes forward, and a transparent protection member 6 with a sloped front surface is provided above the protrusion 5 to protect the distance measurement light receiving window 3.4. There is. On the right side of the protruding part 5 when viewed from the user side, a grip part 7 is formed by embedding an elastic member having several vertical grooves in the front surface. A release button 8 is provided above the grip portion 7.

Further, a zoom finder window 9 is arranged at the upper left side of the camera body 1 when viewed from the user side, and a strobe window 10 is further arranged to the left of the zoom finder window 9. At the front edges of the upper and lower surfaces of the camera body 1, locking grooves 11 and 12 for mounting the conversion lens frame 21 are provided on the camera body 1.
are formed parallel to the front surface of each. Further, a detection hole 13 is provided below the protrusion 5, that is, near the lower end of the front surface of the camera body 1, for the camera to detect that a conversion lens frame is mounted. There is.

On the other hand, the conversion lens frame 21 is shown in FIG. 4(A).
, As shown in (B), a rectangular lens holding part 22
A conversion lens 23 consisting of an appropriate number of lens groups (for example, two lenses 23 a and 23 b as shown in FIG. 6) is held in the lens holder 23 . The entire body is integrally molded from a relatively elastic member such as synthetic resin. The shape of the rear side of the lens holding portion 22 is such that it fits into the protrusion 5 of the camera body 1. At the rear end of the upper surface of the lens holding portion 22, a transparent protection member 6 is provided along the slope of the transparent protection member 6 of the camera body 1.
Support pieces 24a24b supported by the left and right side edges are integrally formed, and the upper ends of both support pieces 24a24b are integrally connected by a locking piece 25 parallel to the upper surface of the lens holder 22.

Therefore, above the lens holding part 22, A11l
Window portion 27 for not obstructing light incident on the distance light receiving windows 3 and 4
is formed. The tip of the locking piece 25 is bent vertically downward to form the locking groove 1 on the top surface of the camera body 1.
1 is a locking claw 25a that fits into the locking claw 25a. A release projection 28 for removing the conversion lens frame 21 from the camera body 1 is formed in the middle portion of the upper surface of the locking piece 25. In addition, the rear end of the lower surface of the lens holding portion 22 further extends rearward to form a locking piece 26, and the tip of the locking piece 26 is bent vertically upward and attached to the camera body 1.
It has a locking pawl 26a that fits into the locking groove 12 on the lower surface of the holder. Further, in the lower part of the lens holding portion 22 of the conversion lens frame 21 on the back side facing the protrusion 5 of the camera body, the detection hole 13 is provided when the conversion lens frame 21 is attached to the camera body 1. (Figure 3 (
13)" (see Fig. 4 (13)).
) is formed.

The conversion lens frame 21 is first inserted into the protruding portion 5 of the camera body 1 with the locking claw 26a at the lower end inserted into the locking groove 12 on the bottom surface of the camera body 1.
When the locking claw 25a at the upper end is located at the upper end of the transparent protection member 6 of the camera body 1, the conversion lens frame 21 is rotated using the locked lower end as a pivot point. When the supporting pieces 24a and 24b are slightly bent due to their elasticity, the locking claw 25a at the upper end rides on the top surface of the camera body 1, and then the locking claw 25a rides on the top surface of the camera body 1. The conversion lens frame 21 reaches the position of the locking groove 11 and is fitted into the locking groove 11, whereby the conversion lens frame 21 becomes attached to the camera body 1 (see FIG. 2).

When the conversion lens frame 21 is attached to the camera body 1 in this manner, the protrusion 29 fits into the detection hole 13 of the camera body 1. By the way, inside this detection hole 13, as shown in FIG.
a exists. The switch actuating member 14 is made of a relatively elastic member such as synthetic resin and has a thin L-shaped cross section, and its lower side is fixed to the inside of the protrusion 5 of the camera body 1 by caulking or the like. By being
The other side is located inside the detection hole 13, and the protrusion that is formed on the other side and becomes the pushing part 14a fits into the detection hole 13, and dust normally enters from this detection hole 13. It prevents A switch 15 for detecting attachment of a conversion lens is disposed behind the switch actuating member 14, and an operator 15a of the switch 15 is connected to the switch actuating member 1.
It faces the other side having the pushing portion 14a of No. 4. Therefore, the conversion lens frame 21 is attached to the camera body 1.
When the two projections are fitted into the detection hole 13, the projection 29 pushes the pusher 14a and pushes the switch actuating member 1, as shown in FIG.
4, the other side of the switch 15 is pushed and bent backward, which pushes and moves the operator 15a of the switch 15 by a predetermined stroke, turning on the switch 15 and confirming that the conversion lens frame 21 is attached to the camera body 1. Detect.

Here, the conversion lens frame 21 is either a wide conversion lens frame or a teleconversion lens frame, and therefore the switch 15 is simply turned on and off when the conversion lens frame 21 is attached or not attached. However, in this embodiment, either a wide conversion lens frame or a teleconversion lens frame can be used as the conversion lens frame 21 attached to the camera body 1, so that the conversion lens The amount of protrusion of the protrusion 29 of the frame 21 is different. For example, the amount of protrusion of the protrusion 29 is set to be larger in the teleconversion lens frame than in the wide conversion lens frame. Therefore, when the conversion lens frame 21 attached to the camera body 1 is a wide conversion lens frame, the operator 15a of the switch 15 is moved to the predetermined first position.
The straw is pushed in for two minutes, and in the case of a teleconversion lens frame, the operator 15a of the switch 15 is pushed in a predetermined second stroke deeper than the first stroke.

The output state of this switch 15 differs depending on whether the amount of depression of the operator 15a is the first stroke or the second stroke. In other words, this switch 15 is activated when the conversion lens frame 21 is attached to the camera body 1.
It is determined whether the conversion lens frame 21 is a wide conversion lens frame or a teleconversion lens frame, and the output state is switched.

FIG. 1 shows the configuration of block I1 of the electric circuit within the camera body 1. As shown in FIG. The output state of the switch 15 is input to a control means 32 consisting of a microcomputer. Further, the output of the focal length (zoom value) detection means 33 is input to the control means 32 .

When the control means 32 detects that the conversion lens frame 21 is mounted on the camera body 1 based on the output state of the switch 15, it determines whether the mounted conversion lens frame 21 is a wide conversion lens frame or a teleconversion lens frame. Different control signals are sent to the zoom lens drive circuit 34 depending on the zoom lens drive circuit 34. When the tube-packed conversion lens frame 21 is a wide conversion lens frame, the zoom lens drive circuit 34 operates the photographing lens unit 35 according to the wide end control signal from the control circuit 32.
When the conversion lens frame 21 is a teleconversion lens frame, the zoom lens driving circuit 3 is driven by the telephoto end control signal.
4 drives the zoom lens in the photographic lens unit 35 to the telephoto end. A zoom end such as a wide end or a telephoto end is detected by the output of the focal length detection means 33.

The photographing lens unit 35 is constructed as shown in FIG. In FIG. 7, a focus frame 41 having a focus lens group L1 is attached to the outer periphery of the front end of a fixed frame 42 by screwing a helicoid screw, and a zoom ring 43 is attached to the outer periphery of the fixed frame 42 to prevent movement in the optical axis direction. Regulation part 42a
and is rotatably fitted while being regulated by a regulating frame 44, which is a separate member. Variator lens group 2. Variator frame 4 integrated with each compensator lens group L3
5. The compensator frame 46 fits into the inner periphery of the fixed frame 42, and the zoom pins 45 are implanted in the respective frames 45 and 46.
a, 46a are straight grooves 47 parallel to the optical axis O of the fixed frame 42
A cam groove 4 formed on the inner circumferential surface of the zoom ring 43 through the
8.49 is fitted. A beam lens group L4 is fixed near the rear end of the fixed frame 42. A gear portion 50 is formed on the outer periphery of the zoom ring 43, and the gear portion 50 meshes with a pinion gear 53 fixed to the output shaft of a zoom DC motor 52 in the zoom lens drive circuit 34 via an idle gear 51. There is. Therefore, the zoom DC motor 52 is now driven, and the pinion gear 53. Idol gear 51. When the zoom ring 43 rotates via the gear part 50,
The zoom pin 45a of the variator frame 45 and the zoom pin 46a of the compensator frame 46 move in the optical axis direction according to the shapes of the cam grooves 48 and 49, respectively. That is, when the zoom DC motor 52 is driven in one direction,
The variator frame 45 and the compensator frame 46 are zoomed to the wide end as shown in FIG. ), zoom to the telephoto end.

A gear portion 54 is also formed on the outer periphery of the focus frame 41, and the gear portion 54 meshes with a pinion gear 57 fixed to the output shaft of an AF stepping motor 56 via an idle gear 55. Therefore, the AF stepping motor 56 is driven, and the pinion gear 57. Idol Gear 55. When the focus frame 41 rotates via the gear portion 54, the focus frame 41 is extended or retracted relative to the fixed frame 42 in the optical axis direction.

A flange 43a is formed at the rear end of the zoom ring 43 which is regulated by the regulating member 44, and a conductive substrate 58 is provided on the rear end surface of the flange 43a to form the focal length detection means 33 (see FIG. 1). is formed. The focal length detection means 33 is constructed as shown in FIG. In FIG. 9, conductive patterns 59 made of semicircular arc-shaped resistors are formed on a conductive substrate 58, one end 59a of the five conductive patterns is grounded, and the other ends 59b1 . :Voltage Vrcf
is applied. Contact piece 6 provided on a fixed part (not shown)
0 is in constant contact with the conductive pattern 59.

Therefore, when the zoom fr:
It is converted into a digital value by a converter 61 and input to the control means 32.

FIG. 10 is a flowchart of the program of the control means 32 shown in FIG. 1. The operation of this embodiment will be explained using this flowchart.

When the conversion lens frame 21 is installed in the camera body 1, the conversion lens frame 21 is installed depending on the output state of the conversion lens attachment detection switch 15.
determines whether it is a wide conversion lens frame or a teleconversion lens frame, and if it is a wide conversion lens frame, drives the zoom DC motor 52 in one direction to close the zoom lens, that is, the variator lens group L2 and the compensator lens. The group L3 is moved to the wide side (see FIG. 8(A)). Focal length detection means 33
When it is detected by the output that the zoom lens has reached the wide end, the drive of the motor 52 is stopped and the process ends. Also, if the mounted conversion lens frame 21 is a tele conversion lens frame, the zoom DC motor 52 is driven in the other direction to move the zoom lens to the tele side (
(See Figure 8(B)). When it is detected from the output of the focal length detection means 33 that the zoom lens has reached the telephoto end, the driving of the motor 52 is stopped and the process ends.

In this way, when the conversion lens frame 21 is attached to the camera body 1, the zoom lens in the camera body 1 is driven to the wide end or the tele end depending on whether the conversion lens frame 21 is a wide conversion lens frame or a tele conversion lens frame. Therefore, there is no need for the user to recognize this and switch the zoom state each time, making the use of the conversion lens frame 21 convenient.

Note that, as described above, the conversion lens frame 21 attached to the camera body 1 may be only one of the wide conversion lens frame and the teleconversion lens frame.

[Effects of the Invention] As described above, according to the present invention, when a conversion lens is attached to a camera body, the focal length of the photographing lens of the camera body is switched to a predetermined value accordingly, and the preferred shooting is automatically performed. become a state.

[Brief explanation of the drawing]

Fig. 1 is a block diagram of an electric circuit in an embodiment of a camera to which the present invention is applied; Fig. 2 is a perspective view of a conversion lens frame attached to the camera body; Fig. 3 (A) and (B). 4(A) and (B) are perspective views of the conversion lens frame as seen from the front and rear, respectively. FIG. 6 is a longitudinal side view of the main part of the camera body for detecting the attachment of a conversion lens. FIG. 8(A) and (B) are views showing the zoom lens group in FIG. 7 moved to the wide-angle side and the telephoto side, respectively; FIG. 9 is a perspective view showing the configuration of the focal length detection means in the camera body, and FIG. 10 is a flowchart showing the operation of the program in the control means in FIG. 1. 15... Conversion lens attachment detection switch (detection means) 32... Control means (means for adjusting lens position) 33...... Focal length detection means 34...
...Zoom lens drive circuit (means for adjusting lens position)

Claims (1)

[Claims] (1) A detection means for detecting that a conversion lens is attached, and a means for adjusting the lens position in response to the output of this detection means so as to set the focal length of the photographing lens to a predetermined value corresponding to when the conversion lens is used. A camera equipped with the following.