GB2372828A

GB2372828A - Power supply between a camera body and an interchangeable lens controller and memory

Info

Publication number: GB2372828A
Application number: GB0203904A
Authority: GB
Inventors: Yukio Uenaka; Hiroyuki Takahashi; Masahiro Kawasaki
Original assignee: Asahi Kogaku Kogyo Co Ltd
Current assignee: Pentax Corp
Priority date: 2001-02-19
Filing date: 2002-02-19
Publication date: 2002-09-04
Anticipated expiration: 2022-02-19
Also published as: DE10206913A1; GB2372828B; GB2372827B; DE10206948A1; GB2372829B; FR2826741A1; FR2826740B1; GB0203904D0; GB2372827A; DE10206913B4; FR2821171A1; DE10206947B8; FR2821171B1; GB0203906D0; GB2372829A; GB0203903D0; DE10206947B4; GB2374154A; DE10206947A1; FR2826741B1

Abstract

A camera system includes a photographing lens (200a) having a lens memory (221) and/or a lens controller (211a), and a camera body (100) including a body controller (111) which can communicate with the lens memory and/or the lens controller. A first power and a second power can be supplied to the photographing lens. The lens memory and the lens controller operate with the first power and the second power, respectively, when the photographing lens is mounted to the camera body. The body controller supplies the first power to the photographing lens to drive the lens memory to read data from the lens memory, and subsequently disables the lens memory and supplies the second power to the lens controller so that the body controller and the lens controller communicate with each other if the body controller determines, from the lens data, that the photographing lens includes the lens controller.

Description

A CAMERA SYSTEM HAVING A COMMUNICATION SYSTEM BETWEEN A

CAMERA BODY AND A PHOTOGRAPHING LENS

The present invention relates to a camera system having a camera body and a photographing lens which is detachably attached to the camera body, and having a communication system between the camera body and the 10 photographing lens.

Power zoom lenses (motorized zoom lenses) with an image sizó-.track'.ng mode,:. in which the camera can automatically zoom the lens to constantly capture the 15 object at a pre-set image size regardless of the distance to the object, within the constraints of the focal length range, are known in the art. In recent camera systems having a camera body and an interchangeable photographing lens which.is-detachably attached to the camera body, if 20 the above-described type of power zoom lens with the image size tracking mode.is employed,.the camera body prepares only data necessary for a CPU of the photographing lens to perform operations thereof in the image size tracking mode, and transmits such data to the photographing lens 25 together with various control commands.

- 2 - However, according to such a data transmission system of the camera system, if the development of an interchangeable photographing lens having one or more additional functions (e.g., a lens autofocus function) S is intended, the camera body to which the photographing lens is mounted will need to prepare camera-status data necessary for the photographing lens to operate for each of all the functions of the photographing lens. This complicates various communication processes and controls 10 of the camera system. On the other hand, if an interchangeable photographing lens having one or more new functions is mounted to a conventional type camera body, it is often the case that such new functions cannot be used and may cause the camera body to malfunction.

15 Accordingly, the development of an interchangeable photographing lens having one or more new functions is difficult in conventional camera systems.

20 An object of the present invention is to provide a camera system having a camera body and a photographing lens which is detachably attached to the camera body, and includes a communication system between the camera system and the photographing lens, wherein the camera system is designed 25 so that the degree of freedom in further developing a

photographing lens so as to have one or more additional new functions is increased, to thereby increase the general compatibility between preexisting and newly developed photographing lenses for the camera body.

S For example, in an embodiment, a camera system is provided, including a photographing lens including at least one of a lens memory, in which lens data on the photographing lens is stored, and a lens controller which controls operations of the photographing lens; and a 10 camera body including a body controller which can communicate with at least one of the lens memory and the lens controller; a first power which can be supplied to the photographing lens; and a second power which can be supplied to the photographing lens. The photographing 15 lens can be mounted to; and dismounted from, the camera body. The lens memory and the lens controller operate with the first power and the second power, respectively, when the photographinglens is mounted to the camera body.

The body controller supplies the first power to the 20 photographing lens to drive the lens memory to read out the lens data from the lens memory when the photographing lens is mounted to the camera body, and subsequently disables the lens memory and supplies the second power to the lens controller so that the body controller and 25 the lens controller communicate with each other in the

4 - case where the body controller determines, from the lens data read out of the lens memory, that the photographing lens includes the lens controller.

The camera body can include a body communication 5 line, a first body powerline and a second body power line.

The photographing lens can include a lens communication line, a first lens power line, and a second lens power line which are connected with the body communicationline, the first body power line and the second body power line, 10 respectively, when the photographing lens is mounted to the camera body. The camera body and the photographing lens can communicate with each other via the body communication line and the lens communication line. The camera body can supply the first power to the 15 photographing lens via the first body power line and the first lens power line. Similarly, the camera body can supply the second power to the photographing lens via the second body power line and the second lens power line.

It is desirable for the body controller to include 20 a control line for changing a state of the lens memory between an enabled state and a disabled state.

The camera body can transmit a first command, for making the lens controller enter a sleep mode, to the lens controller via the body communication line and the lens 25 communication line, the lens controller entering the

_ - 5 - sleep mode upon receiving the first command; and the camera body can transmit a second command, for making the lens controller come out of the sleep mode, to the lens controller via the body communication line and the lens 5 communication line, the lens controller coming out of the sleep mode upon receiving the second command.

It is beneficialfor the power capacity of the second power to be substantially greater than the power capacity of the first power.

10 Alternatively, a camera body is provided to which a photographing lens can be mounted and dismounted, the photographing lens having at least one of a lens memory, in which lens data on the photographing lens is stored, and a lens controller which controls operations of the 15 photographing lens, the camera body including a body controller which can communicate with at least one of the lens memory and the lens controller; a first power which can be supplied to the photographing lens; and a second power which can be supplied to the photographing lens.

20 The lens memory and the lens controller operate with the first power and the second power, respectively, when the photographing lens is mounted to the camera body. The body controller supplies the first power to the photographing lens to drive the lens memory to read out 25 the lens data from the lens memory when the photographing

6 - lens is mounted to the camera body, and subsequently disables the lens memory and supplies the second power to the lens controller so that the body controller and the lens controller communicate with each other in the 5 case where the body controller determines, from the lens data read out of the lens memory, that the photographing lens includes the lens controller.

It is beneficial for the camera body to further include a body communication line, a first body power line 10 and a second body power line, and the photographing lens to include a lens communication line, a first lens power line, and a second lens power line which are connected with the body communication line, the first body power line and the second body power line, respectively, when IS the photographinglens is mounted to the camera body. The camera body and the photographing lens communicate with each other via the body communication line and the lens communication line. The camera body supplies the first power to the photographing lens via the first body power 20 line and the first lens power line. The camera body supplies the second power to the photographing lens via the second body power line and the second lens power line.

The body controller can include a control line for changing a state of the lens memory between an enabled 25 state and a disabled state.

7 - The camera body can transmit a first command, for making the lens controller enter a sleep mode, to the lens controller via the body communication line and the lens communication line, the lens controller entering the 5 sleep mode upon receiving the first command; and the camera body can transmit a second command, for making the lens controller come out of the sleep mode, to the lens controller via the body communication line and the lens communication line, the lens controller coming out of the 10 sleep mode upon receiving the second command.

A photographing lens which can be mounted to and dismounted from a camera body, can be provided, including a lens memory in which lens data on the photographing lens isstored,and alens controller which controls operations 15 of the photographing lens. The lens memory and the lens controller operate with a first power and a second power which are supplied from the camera body, respectively, when the photographing lens is mounted to the camera body.

The lens memoryis driven tocutputthelens date therefrom 20 to the camera body under control of the camera body when the camera body supplies the first power tothelens memory The lens memory is disabled, so that the lens controller communicates with the camera body, when the camera body supplies the-second power to the lens controller.

25 The photographing lens can further include a lens

À 8 - communication line, a first lens power line, and a second lens power line which are respectively connected with associatedlines of the camera body when the photographing lens Is mounted to the camera body. The photographing 5 lens communicates with the camera body via the lens communication line; the photographing lens receives the first power from the camera body via the first lens power line;andthephotographinglens receives the second power from the camera body via the second lens power line.

10 It is desirable for the photographing lens to further include a control line for changing a state of the lens memory between an enabled state and a disabled state. A camera system can be provided, including a camera 15 body and a photographing lens which can be mounted to and dismounted from the camera body; wherein the photographinglens includes at least one of a lens memory, in which lens data on the photographing lens is stored, and en electronic device; wherein the camera body includes 20 a body.controller which can communicate with the lens memory, a first power which can be supplied to the photographing lens, and a second power which can be supplied to the photographing lens, a power capacity of the second power being greater than the first power. The 25 lens memory and the electronic device operate with the

- 9 first power and the second power, respectively, when the photographing lens is mounted to the camera body. The body controller supplies the first power to the photographing lens to drive the lens memory to read out 5 the lens data from the lens memory when the photographing lens is mounted to the camera body. The body controller supplies the second power to the electronic device in the case where the body controller determines, from the lens data read out of the lens memory, that the photographing 10 lens includes the electronic device.

Examples of the present invention will be described below in detail with reference to the accompanying drawings in 15 which: Figure 1 is a block diagram of various elements of control systems of a camera body and a photographing lens of anSLR camera system haying a communication system between the camera body and the photographing lens 20 embodying. -the present invention; Figure 2 is a block diagram of various elements of the control system of the camera body; Figure 3 is a block diagram of various elements of a communication control system of the photographing 25 lens;

- 10 Figure 4 is a block diagram of various components of a photographing lens which is provided with a lens controller which operates with a first power, and a peripheral circuit which operates with a second power; S Figure 5 is a block diagram of various components of a photographing lens which is provided with a lens controller and a peripheral circuit both of which operate with the first power; Figures 6A and 6B show flow charts for the first 10 portion of a main process of the camera body to which the present invention is applied; Figure 7showsaflow chart for the remaining portion of the main process of the camera body, shown in figures 6A and 6B; 15 Figure 8A is a flow chart for a communication identification process including of an old-type communication process and a new-type communication setting request process of the camera body; Figure 8B is a flow chart for operations of a 20 photographing lens which are performed in accordance with operations of the new-type communication setting request process of the camera body; Figure 9 is a flow chart for the new-type communication setting request process of the camera body; 25 Figure 10 is a flow chart for a camera state

- 11 -

information setting process of the camera body; Figure 11 is a flow chart for an image-shake compensation data setting process of the camera body; Figure 12A is a block diagram of various 5 elements of a control system of the first embodiment of the photographing lens which incorporates an image-shake compensation device; Figure 12B is a conceptual diagram of a compensation lens (an image-stabilizing optical system) LC of the 10 image-shake compensation device; Figure 13 is a flow chart for a main process of a first embodiment of the photographing lens; Figure 14 is a flow chart for a new-type communication setting process of the photographing lens; 15Figure 15 is a flow chart for a lms-timer interrupt process of the first embodiment of the photographinglens; Figure 16 is a flow chart for the first half of an inverse-INT interrupt process of the first embodiment of the photographing lens; 20Figure 17 is a flow chart for the remaining half of the inverse-INT interrupt process of the first embodiment of the photographing lens; Figure 18 is a timing chart for a communication identification process from the moment the main switch 25 of the camera body is turned ON to the moment immediately

- 12 after the commencement of the new-type communication process; Figure l9A is a timing chart for a handshake operation performed between the camera body and the 5 photographing lens at the commencement of the newtype communication process; Figure l9B is a timing chart for a handshake operation performed between the camera body and the photographing lens at the commencement of the new-type 10 communication process; Figure 20 is a timing chart for an old type communication process that is performed between the camera body and the photographing lens; Figure 21A is a timing chart for communication in 15 the new-type communication process that is performed between the camera body and the photographing lens; Figure 21B is a timing chart for communication in the new-type communication process that is performed between the camera body and the photographing lens; 20 Figure22 is a block diagram of various elements of a comm.unica.tion.control..sy.stem of a second embodiment of a photographing lens which incorporates a lens AF system; Figure 23 is a flow chart for a main process of the 25 second embodiment of the photographing lens;

- 13 Figure 24 is a flow chart for a lms-timer interrupt process of the second embodiment of the photographing lens; Figure 25 is a flow chart for the first half of an 5 inverse-INT interrupt process of the second embodiment of the photographing lens; and Figure 26 is a flow chart for the remaining half of the inverse-INT interrupt process of the second embodiment of the photographing lens.

Figure 1 shows various elements of control systems of a camera body and an interchangeable photographing lens of an embodiment of an SLR camera system to which the present invention is applied. A camera body 100 is provided with a body CPU (body controller) 111 serving as a controller which comprehensively controls the overall operations of the SLR camera system. The camera body 100 is provided with 20 a body mount 103 to which a photographing lens 200 is mounted. A group of communication/control contacts (body communication line) 104 are provided on the body mount 103. The group of communication/control contacts 104 consists of six contactsin this particular embodiment 25 One of the six contacts serves as a power contact

- 14 (constant-voltage contact) for supplying a first power from the camera body 100 to low power elements (e.g., a ROM) provided in the photographing lens 200 to drive the low power elements, while another one of the six contacts 5 serves as a control terminal via which a ROM provided in the photographing lens 200 is enabled or disabled (i.e., turned ON or OFF). A power contact 105 (VPZ) via which a second power is supplied from the camera body 100 to the photographing lens 200 is provided on the body mount 10 103. The power capacity of the second power that is supplied from the power contact 105 (vPz) to the photographing lens 200 is substantially greater then that of the first power that is supplied from the aforementioned constant-voltage contact of the group of 15 communication/controlcontacts104. Although the supply voltage of the second power is greater than the supply voltage of the first power, the supply voltage of the second power can be identical to the supply voltage of the first power or even smaller than the supply voltage 20 of the first power as long as the power capacity of the second power is substantially greater than the power capacity of the first power.

Although it is desirable that the group of communication/control contacts 104 and the power contact 25 105 (VPz) be provided on the body mount 103, the group

of communication/control contacts 104 and the power contact 105 (VPZ) can be provided behind the body mount 103 in a mirror box of the camera body 100, in which a quick-return mirror is positioned. Alternatively, it is 5 possible that the group of communication/control contacts 104 be provided on the body mount 103 and the power contact 105 (VPZ) be provided behind the body mount 103 in the mirror box of the camera body 100.

10 Figure 2 shows various elements of the control system of the camera body 100. A photometering switch SWS, a release switch SWR, a main switch SWMAIN, an image-shake compensation switch SW1 and an AF switch SWAF are connected to the body CPU 111, which serves as a controller that comprehensively controls the overall operations of the SLR camera system.

The power to peripheral circuits of the camera body 100 is turned ON and OFF when the main switch SWMAIN is turned ON and OFF, respectively. The power from a battery 20 (power supply) 113 accommodated in the camera body 100 is supplied to each peripheral circuit of the camera body 100 via a regulator (DC/DC converter) 116 when the main switch SWMAIN is turned ON, and the power from the battery 113 to each peripheral circuit of the camera body 100 is 25 cut off when the main switch SWMAIN is turned OFF. The

- 16 body CPU lllis always supplied with power from the battery 113 via the regulator 116, so that the body CPU 111 is in operation at all times.

The camera body 100 is provided with a strobe circuit 5 121, a mirror circuit 123, a shutter circuit 125, a film-winding circuit 127, a photometering circuit 129 and a distance measuring circuit 131, which are all connected to the body CPU 111. The photometering switch SWS is turned ON when a release button (not shown)in the camera 10 body is depressed by half a step, and the release switch SWR is turned ON when the release button is fully depressed Immediately after the photometering switch SWS is turned ON, the body CPU 111 actuates the photometering circuit 129 to perform a photometering operation. At the same 15 time, the body CPU 111 calculates and sets an optimum shutter speed and an optimum aperture value (f-number), and actuates the strobe circuit 121 to perform a strobe charging process as needed. Furthermore, the body CPU 111 actuates the distance measuring circuit 131 to 20 determine an amour,t of defocus, to perform an autofocus process if en autofocus mode has been set via the AF switch SWAP. Immediately after the release switch SWR is turned ON, the body CPU 111 actuates the shutter circuit 125 to drive a focal plane shutter mechanism (not shown) to 25 expose a film frame. Upon completion of an exposure, the

body CPU 111 actuates the film-winding circuit 127 to wind up film by one frame and at the same time to charge the focal plane shutter mechanism.

When the new-type photographing lens (e.g., a KAF 5 III type photographing lens having a lens CPU, a lens ROM, and all of the communication functions which correspond with those of the camera body 100) 200 is mounted to the camera body 100, during the time the main switch SWMAIN is ON, the: body CPU 111 turns ON a switch circuit 115 to 10 supply the power from the battery 113 as the aforementioned second power to the photographing lens 200 via the power contact 105 (VPZ) of the camera body 100 and associated power contact 205 (VPZ) of the photographing lens 200, which is in contact with the power 15 contact 105 (VPZ). In addition, if an image-shake compensation mode has been set via the image-shake compensation switch Sol, and if the photographing lens 200 is provided with an image-shake compensation device, the body CPU 111 outputs an image-shake compensation 20 command to the photographing lens 200 via lens communication to make the photographing lens 200 perform an image-shake compensation operation. If the photographing lens 200 mounted to the camera body 100 is further provided therein with a lens AF system, the body 25 CPU Ill outputs defocus data (e.g., the amount of driving

of an AF motor 261 (see Figure 12A) and the direction of driving of the AF motor 261 in the photographing lens 200) to the photographing lens 200 via lens communication to make the photographing lens 200 perform a lens autofocus S process As shown in Figure 12A, an encoder 231, an AF motor (focusing lens driving device) 261, an AF lens group (focusing lens group) Lf, and a lens CPU 211 constitute a focus adjusting system (electrical component).

10 The photographing lens 200 is provided onthelens mount 203 thereof with a group of communication/control contacts (lens communication line) 204 and the power contact 205 (VPz). The group of communication/control contacts 2 4-and the power contact 205 (VPZ) come into IS contact with the group of communication/control contacts 104 and the power contact 105 (VPz) of the camera body 100, respectively, when the photographing lens 200 is mounted to the body mount 103 of the camera body 100 via the lens mount 203. The photographing lens 200 is 20 provided therein with the lens CPU (LCPU/lens controller/electronic device) 211, a lens ROM (LROM/lens memory/nonvolatile lens memory! 221, the encoder 231 and a peripheral circuit 241. Various modes and parameters are stored in the lens ROM 221. A current focal length 25 (zoom code) and a photographic distance are detected via

19 the encoder 231. The peripheral circuit 241 includes, for example, as shown in Figure 12A, image-shake compensation motors (X-motor 254 and Y-motor 257), the AF motor 261, and a power zoom motor (power zoom driving 5 device) 264, which are all provided in the photographing lens 200. Note that the power zoom motor 264 is connected to a lens group Lz, and the lens group Lf and the lens group Lz constitute at least part of a zoom lens system of the photographing lens 200.

10 The group of communication/control contacts 104 of the camera body 100 consists of six contacts: a first contact 104a (Fminl/Inverse-SCKL), a second contact104b (Fmin2/ DATAL), a third contact 104c (Fmin3/ RESL), a fourth contact 104d (CONTL), a fifth contact 104e (Fmaxl/ 15 Inverse-FBL) and a sixth contact 104f (Fmax2/ Inverse-FLB). Likewise, the group of communication/control contacts 204 of the photographing lens 200 consists of six contacts: a first contact 204a (Fminl/ Inverse-SCKL), a second contact 204b (Fmin2/ 20 DATAL), a third contact 204c (Fmin3/ RESL), a fourth contact 204d (CONTL), a fifth contact 204e (Fmaxl/ Inverse-FBL) and a sixth contact 204f (Fmax2/ Inverse-FLB) which come into contact with the first through sixth contacts 104a through 104f respectively, 25 when the photographing lens 200 is mounted to the camera

- 20 body 100.

A power line from port P13 of the body CPU 111 to the fourth contact 104d constitutes a first body power line for supplying the first power to the photographing 5 lens 200. The powerline from the battery 113 to the power contact 105 (via the switch circuit 115) constitutes a second body power line for supplying the second power to the photographing lens 200. The power line from the fourth contact 204d to a port CONT of the lens ROM 221 10 constitutes a first lens power line for supplying power from the camera body 100 to the photographing lens 200.

The power line from the power contact 205 to a regulator 243 and to a switching circuit 242 constitutes a second lens power line for supplying power from the camera body IS 100 to the lens CPU 211. As shown in Figure 1, the second power that is output from the camera body 100 to be input to the photographing lens 200 via the power contacts 105 and 205 (VPZ) is supplied to the lens CPU 211 via the regulator 243 of the photographing lens 200 and also to 20 the peripheral circuit 241 via a switching circuit 242 of the photographing lens 200. The lens ROM 221 of the photographing lens 200 operates with constant voltage power (the first power) supplied from the fourth contact 204d (CONTL), whereas the lens CPU 211 operates with the 25 second power having a large power capacity supplied from

- 21 the power contact (VPZ) 205. The processing speed and the throughput of a CPU is generally proportional to the power consumption of the CPU. Accordingly, in the present embodiment of the SLR camera system to which the 5 present invention is applied, providing the second power having a large power capacity to the photographing lens 200 makes it possible for the photographing lens 200to be provided therein with not only a CPU which achieves a high throughput, but also high power components (i.e., 10 components which require a large current) such as a lens motor and an image-shake compensation device.

Figure 3 is a block diagram of various elements of a communication control system of the photographing lens 200. The first contact 204a (Fminl/ Inverse-SCKL), the second contact 204b (Fmin2/ DATAL), the third contact 204c (Fmin3/ RESL), and the fourth contact 204d (CONTL) of the group of communication/control contacts 204, of the photographing lens 200, are connected to four ports Inverse-SCK, SI0, RES, and CONT of the lens ROM 221, 20 respectively.

The port RES of the lens ROM 221 serves as an input port via which the lens ROM 221 inputs a reset signal that changes the state of the lens ROM 221 from a disabled state to an enabled state. The port SIO of the lens ROM 221 25 serves as an I/O port for serial communication. The port

22 Inverse-SCK of the lens RQ -221 serves as an input port via which the lens ROM 221 inputs a clock signal for communication from the camera body 100. The port CONT of the lens ROM 221 serves an input port via which the 5 lens ROM 221 inputs a constant voltage power (the first power) from the camera body 100.

The lens ROM 221 operates in accordance with the first power (constant voltage power), which is supplied from the camera body 100 to be applied to the port CONT 10 of the lens ROM 221. The lens ROM 221 is set to change the state of the lens ROM 221 from a disabled state to an enabled state by a reset signal, which is input via the port RES of the lens ROM 221 to enter the enabled state.

Lens data written in the lens ROM 221 is read out therefrom 15 to be output to the camera body 100 via the port SIO of the lens ROM 221 in synchronization with the crock signal input, via-the port Inverse=SCK. The port RES of the lens ROM 221 and the third contact 204c (Fmin3/ RESL), which is connected to the port RES, also serve as a control line 20 for changing the state of the lens ROM 221 between an enabled state and adisabled state Namely, the lens ROM 221 operates while the first power is being supplied to the fourth contact 204d (CONTL), and the lens ROM 221 is set to change the state thereof from a disabled state to 25 an enabl d.state if the level of the third contact 204c

- 23 Liming/ RESL) falls to a low level, and the lens ROM 221 is set to change the state of the lens ROM 221 from an enabled state to a disabled state if the level of the third contact 204c (Fmin3/ RESL) rises to a high level. The 5 timing chart thereof is shown in Figure 20.

As' shown'i'n Figure 3, the' lens CPU 211 is provided with eight ports RXD, TXD, TXDEN, Inverse-SCK, Pee, Pet, INT and VCC, and the photographing lens 200 is provided with first through fourth high input voltage proof Schmitt 10 inverters VCC1, VCC2, VCC3 and VCC4. The first contact 204a (Fminl/ Inverse-SCKL) is connected to the port Inverse-SCK of the lens CPU 211 via the second and third Schmitt inverters VCC2 and VCC3, and the second contact 204b (E'min2/ DATAL) is connected to the port RXD of the lens CPU 211 and also to each of the two ports TXD and TXDEN of the lens CPU 211 via a first I/O protection circuit 212.

The port RXD of the lens CPU 211 serves as a data input port. The port TXD of the lens CPU 211 serves as 20 a data output port. The port TXDEN of the lens CPU 211 serves as a control port via which the lens CPU 211 determines 'whether data can be output from the port TXD of the lens CPU 211. The port Inverse-SCK of the lens CPU 211 serves as an input port via which the lens CPU 25 211 inputs a clock signal for communication from the

- À 24 camera body 100.

When the control port TXDEN of the lens CPU 211 is at a high level, if the level of a data output port TXD of the lens CPU 211 rises to a high level, a field effect

5 transistor (FET) of the first I/O protection circuit 212 is turned OFF while a transistor of the first I/O protection circuit 212 is turned ON to thereby cause the level of port 212a to rise to a high level. On the other hand, if the level of the data output port TXD of the lens 10 CPU 211 falls to a low level when the control port TXDEN of the lens CPU 211 is at a high level, the field effect

transistor (FET) of the first I/O protection circuit 212 is turned ON while the transistor of the first I/O protection circuit 212 is turned OFF to thereby cause the 15 level of port 212a to fall to a low level. Therefore, when the control port TXDEN of the lens CPU 211 is at a high level, the level of the data output port TXD of the lens CPU 211 is output from the first I/O protection circuit 212 via port 212ato be input to the second contact 20 204b (Fmin2/ DATAL).

Because each of the field effect transistor (FET)

and the transistor of the first I/O protection circuit 212 is OFF when the control port TXDEN is at a low level, port 212a is in a high impedance state regardless of the 25 level of the data output port TXD of the lens CPU 211.

i - 25 -

The sixth contact 204f (Fmax2/ Inverse-FLB) is connected to each of the two ports P00 and P01 of the lens CPU 211 via a second I/O protection circuit 213, while the fifth contact 204e (Fmaxl/ Inverse-FBL) is connected 5 to the port INT of the lens CPU 211 via the fourth high input voltage proof Schmitt inverter VCC4. The port P00 of the lens CPU 211 serves as an output port while the port P01 of the lens CPU 211 serves as a control port via which the lens CPU 211 determines whether data can be 10 output from the port P00. The port INT of the lens CPU 211 serves as an input port via which the lens CPU 211 inputs an interrupt signal.

When the control port P01 of the lens CPU 211 is at a high level, if the level of the output port P00 of the 15 lens CPU 211 rises to a high level, a field effect

transistor ( FET) of the second I/O protection circuit 213 is turned OFF while a transistor of the second ItO protection circuit 213 is turned ON to thereby cause the level of port 213a to rise to a high level. On the other 20 hand, if the level of the output port P00 of the lens CPU 211 falls to a low level when the control port P01 of the lens CPU 211 is at a high level, the field effect

transistor (FET) of the second I/O protection circuit 213 is turned ON while the transistor of the second I/o 25 protection circuit 213 is turned OFF to thereby cause the

- 26 level of port 213a to fall to a low level. Therefore, when the output port P00 of the lens CPU 211 is at a high level, the level of the output port P00 of the lens CPU 211 is output from the second I/PO protection circuit 213 5 via port 213a to be input to the sixth contact 204f (Fmax2/ Inverse-FLB). Because each of the field effect transistor (FET)

and the transistor of the second I/O protection circuit 213 is OFF when the control port P01 is at a low level, 10 port 21 a is in a high impedance state regardless of the level of the output port P00 of the lens CPU 211.

The power contact 205 (vPE J is connected to the power port VCC of the lens CPU 211 via a regulator 243. The lens CPU 211 operates with constant voltage supplied from 15 the regulator 243 to the power port VCC.

Selection between the communication channel for communication of the body CPU 111 with the lens ROM 221 (i.e., lens ROM communication/old-type communication) and the communication channel for communication of the 20 body CUD 111 with the lens CPU 211 (i.e., new-type communication) depends on a reset signal input to the third contact 204c (Fmin3/ RESL). If the level of the input port RES of the lens ROM 221 rises to a high level, the lens ROM 221 enters a disabled state and the SIO port 25 of the lens ROM 221 enters a high impedance state. This ...

- À 27 makes the. aforementioned new-type lens communication between the body CPU Ill and the lens CPU 211 possible.

The first contact 204a (Fminl/ Inverse-SCKL), the secondcontact204b(Fmin2/DATAL),the third contact204c 5 (Fmin3/ RESL), the fifth contact 204e (Fmaxl/ Inverse-FBL) and the sixth contact 204f (Fmax2/ Inverse-FLB) maintain compatibility with conventional camera systems using interchangeable lenses in which serial commi nicaticr. between camera body and 10 interchangeable lens is performed without using a ROM (lens ROM) provided in the interchangeable lens. For instance, in order to maintain compatibility with a camera body which can obtain the minimum f-number and the maximum f-number from the photographinglens mounted to the camera 15 body, diodes (zener diode) are selectively provided in a manner for making the first, second, third, fifth r.d Saxon contacts 204a, 204b, 204c, 204e and 204f serve as aperture information contacts so that the camera body can input data on the minimum f-number 20 (the f-number at maximum aperture) via the first, second and third contacts 204a, 204b and 204c and so that the camera body can input data on the maximum f-number (the f-number at minimum aperture) via the fifth and sixth contacts 204e and 204f:such that the camera body can 25 distinguish between the m= mmf-n ter and the mu mf-nu erby Piecing

- 28 continuity of each contact via the diodes.

Figure 4 is a block diagram of various components of a photographing lens 200a which is provided with a lens CPU 211a and a peripheral circuit 241a. The lens CPU 211a S operates with the first power supplied from the fourth contact 204d tCONTL),- while cile peripheral circuit 241a operates with power supplied from the power contacts 105 and 205 (VPZ). In the photographing lens 200a shown in Figure 4, the power supplied from the power contacts 105 10 and 205 (VPZ) is supplied to the peripheral circuit 241a via the switching circuit 242.

Figure 5 is a block diagram of various components of a photographing lens 200b which is provided with a lens CPU 211b an-d a peripheral circu t241b. The lens CPU 211b 15 operates with the first power supplied from the fourth contact 204d (CONTL). The photographing lens 200b shown in Figure 5 is not provided with either a power contact or a regulator corresponding to the power contact 205 (VPZ) or the regulator 243, respectively. Each of the 20 lens CPU 211b and the peripheral circuit 241b operates with the first power supplied from the fourth contact 204d (CONTL).

In the photographing lens 200a shown in Figure 4, the camera body 100 supplies the first power and the second 25 power to the fourth contacts 104d and 204d (CONTL) and

- 29 the power contacts 105 and 205 (VPZ), respectively. On the other hand, in the photographing lens 20Ob shown in Figure 5, the camera body 100 supplies only the first power to the fourth contacts 104d and 204d (CONTL).

S Various operations of the camera body 100 and the photographing lens 200 will be hereinafter discussed in detail with reference to the flow charts shown in Figures 6 through 11 and the timing charts shown in Figures 18 through 21B. Figure 6 shows a flow chart for the main 10 process of the camera body 100 which is performed by the body CPU 111. Control enters the main process immediately after the battery 113 is loaded into the camera body 100. The camera body 100 performs both old- type communication (lens ROM communication) and 15 new-type communication between the camera body 100 and the photographing lens 200, whereas the camera body 100 performs only the old-type communication (lens ROM communication) between the camera body 100 and the photographing lens 200 if the photographing lens 200 is 20 of any other type which is not provided with any CPU corresponding to the lens CPU 211 of the photographing lens 200 but provided with only a lens ROM, and which accordingly does not have any communication capability of the photographing lens 200. It should be noted that 25 operations or processes having step numbers bearing a

- 30 prefix"CS"are related to control/opera/ion of the camera body 100 and that operations or processes having step numbers bearing a prefix 'LS" are related to control/operation of the photographing lens 200.

5 Commands for discussion of the present embodiment of the SLR camera system are fisted belong. All the commands listed below are those which are transmitted from the camera body 100 to the photographing lens 200.

10 [COMMANDS TRANSMITTED FROM CAMERA BODY TO LENS IN ORDER

TO COMMAND LENS TO TRANSMIT DATA TO CAMERA BODY]

70: Command for making the photographing lens send a lens status thereof to the camera body.

71: Command for making the photographing lens send 15 a lens status thereof to the camera body and for making the lens CPU enter a sleep mode together with the body CPU. 72: Command for making the photographing lens send information on functions that the photographing lens 20 possesses, such as an image-shake compensation function and a lens autofocus function, to the camera body.

7F: Command for a rear converter.

[COMMANDS FOR DATA TRANSMISSION FROM CAMERA BODY TO LENS]

BO: Command for sending data to the photographing 25 lens.

- 31 B1: Command for sending data to the photographing lens and for making the lens CPU enter a sleep mode.

B2: Command for sending data on a driving-amount for the AF motor provided in the photographing lens to the 5 photographing lens.

[INSTRUCTION COMMANDS TRANSMITTED FROM CAMERA BODY TO

LENS] D0: Command for making the lens CPU enter the sleep mode. 10 D1: Command for turning OFF an image-shake compensation function.

D2: Command for turning ON the image-shake compensation function.

D3: Command for stopping the driving of the AF motor 15 provided in the photographing lens.

D4: Command for resuming the driving of the AF motor provided in the photographing lens.

In the-main process shown in Figure 6, firstly it is determined whether the main switch SWMAIN is ON (step 20 CS101). The operation at step CS101 is repeated until the main switch SWMAIN is turned ON. If the main switch SWMAIN is turned ON (if YES at step CSl01), a communication identification process (i.e., en old-type communication process at step CS103 and a new-type 25 communication setting request process at step CS105) is

- 32 performed. Command 72 is transmitted to the photographinglens toreceivedatatherefrom(stepCS107).

Command 72 commands the lens CPU 211 to output information on the functions that the photographing lens possesses 5 to the body CPU 111. The functions of the photographing lens can include, e.g., an image-shake compensation function, a lens autofocus function and other functions which operate with power (the second power) supplied from the power contacts VPZ. Upon receiving command 72, the 10 lens CPU 211 of the (newtype)photographing lens 200 outputs information on functions that the photographing lens 200 possesses to the body CPU 111. Figure 18 shows a timing chart for the aforementioned communication identification process from the moment the main switch 15 SWMAIN is turned ON to the moment immediately after the commencement of the new-type communication process.

Flqures l9A and l9B each show a timing chart for a handshake operation performed between the camera body 100 and the photographing lens 200 at the commencement of the 20 communication process. Figure 20 shows a timing chart for the old-type communication process. Figures 21A and 21B show timing charts for the new-type communication process. After the operation at step CS107, the body CPU 111 25 sets a lens sleep,flag SLP to "0'' (step CS109). The lens

- 33 sleep flag SLP "1" or "0" indicates that the lens CPU 211 is in the sleep mode (low power operation mode) or not in the sleep mode, respectively. The operations or processes at steps CS103 through CS109 are performed when 5 the main switch SWMAIN is turned from OFF to ON.

Thereafte-, the operations at and after step CS111 are repeated. At step CS111, ON/OFF states of all the switch ports are input. Subsequently, a camera state information 10 setting process is performed(step CS113). In the camera state information setting process, the information on the current states of some specific switches and a flash charging system which is to be transmitted to the lens CPU 211 via the new-type communication is prepared.

15 Subsequently, the old-type communication process is performed (step CS115), and it is determined whether a photographing lens is mounted to the camera body 100 (step CS117). If no photographing lens is mounted (if YES at step CS117), each of the fourth contact 104d (CONTL) and 20 the power contact 105 (VPZ) is set to a low level (step CS119), and control returns to step CS101. If it is determined at step CS117 that a photographing lens is mounted (if NO at step CS117), it is determined whether a new-type flag is "1", i.e., whether the photographing 25 lens currently mounted to the camera body 100 is the

- 34 (new-type) photographing lens 200 (step CS121). The new-type flag "1" indicates that the photographing lens currently mounted to the camera body 100 is the (new type) photographing lens 200. If the new-type flag is 5 "1" (if YES at step CS121), it is determined whether a power hold flag PH is "0", i.e., whether the camera body 100 is not in a power hold state (step CS123). If the power hold flag PH is ' on (if YES at step CS123), it is determined whether the lens sleep flag SLP is "1" (step 10 CS125). If the lens sleep flag SLP is "1" (if YES at step CS125),- control returns to step CS111 since the photographing lens 200 is already in a sleep mode. If it is determined at step CS125 the lens sleep flag SLP is not "1", command B1 is transmitted to the lens CPU 211 15 to make the photographing lens 200 enter the sleep mode (step CS127). Subsequently, the lens sleep flag SLP is setto"l"(stepCS129),andcontrol returns to step CS111.

If it is determined at step CS123 that the power hold flag PH is not "O" (if NO at step CS123), command BO is JO transmitted to the lens CPU 211 to start the lens CPU 211 (step CS131), and the lens sleep flag SLP is set to "O" (step CS133). Subsequently, it is determined whether an image- shake compensating type lens flag is "1", i.e., whether the photographing lens 200 mounted to the camera 25 body 100 is provided with an image- shake compensation

- - 35 device (step CS135). If the image-shake compensating type lens flag is U1" (if YES at step CS135), an image-shake compensation data setting process, in which predetermined flags and data on image-shake compensation 5 are set, is performed (step CS137), and control proceeds to step CS139. If the image-shake compensating type lens flag is not "1" (if NO at step CS135), control skips step CS137 to proceed straight from step CS135 to step CS139.

If it is determined at step CS121 that the new-type flag 10 is not "1", control proceeds straight from step CS121 to step CS139.

At step CS139 it is determined whether a SWMAIN flag is "0", i.e., whether the main switch SWMAIN has been turned from ON to OFF. If it is determined at step CS139 15 that the SWMAIN flag is not '1" (if NO at step CS139), it is determined whether the photometering switch SWS is ON (step CS141). If the photometering switch SWS is not ON (if NO at step CS141), control returns to step CS111.

If the photometering switch SWS is ON ( if YES at step 20 CS141), control proceeds to step CS151, If it is determined at step CS139 that the SWMAIN flag is "1", it is determined whether the new-type flag is "1" (step CS143). If it is determined at step CS143 that the new-type flag is not "1", control returns to step CS101.

25 If it is determined at step CS143 that the new-type flag

is "1" ( i.e., that the (new-type) photographing lens 200 is currently mounted to the camera body 100), it is determined at step CS145 whether a second power flag VpzONCPU is "1", i.e., whether the photographing lens 200 5 mounted to the camera body 100 is of a type which operates with power supplied from the power contact 105 (VPZ). If it is determined at step CS145 that the second power flag VpzONCPU is "1" (if YES at step CS145), the port VPZ is turned OFF, i.e., power supplied to the power contact 105 10 (VPZ) is cut off (step CS147), and control returns to step CSlQ1. If it is determined at step CS145 that the second power flag VpzONCPU is not "1" (if NO at step CS145), control returns to step CS101 since the photographing lens mounted to the camera body 100 does not operate with power 15 supplied from the power contact 105 (VPz).

Operations which are performed after it is determined at step CS141 that the photometering switch SWS is ON will be hereinafter discussed with reference to the flow chart shown in Figure 7.

20 If it is determined at step CS141 that the photometering switch SWS is ON (if YES at step CS141), a photometering operation in which photometric data is input from a photometering sensor and an exposure arithmetic operation are performed in accordance with a 25 currently selected photometering mode and a

- 37 currently selected exposure mode, respectively (step CS151). Subsequently, AF sensor data is input from an AF sensor in accordance with a currently selected AF mode, while a predetermined AF arithmetic operation necessary 5 for attaining an in-focus state is performed in accordance with the input AF sensor data (step CS153).

Subsequently, it is determined whether the new-type flag is "1" (step CS155). If the new-type flag is "1" (if YES at step CS155), it is determined whether a lens 10 AF flag is "1", i.e., whether the photographing lens 200 mounted to the camera body 100 has a lens autofocus function (step CS157). If the lens AF flag is "1" (if YES at step CS157), it is determined whether an AFON flag is "1" (step CS159). The AFON flag "1" indicates that 15 the AF function is ON, i.e., the AF function is in operation. If the AFON flag is "1" (if YES at step CS159), data on a driving amount of an AF lens (focusing lens group) Lf of the photographing lens is transmitted to the lens CPU 211 (step CS161), and subsequently control 20 proceeds to step CS163. If at least one of the new-type flag, the lens AF flag and the AFON flag is not "1", control skips the operation at step CS161 and proceeds to step CS163.

At step CS163 it is determined whether an in-focus 25 state has been obtained. If an in-focus state has not

- 38 been obtained (if NO at step CS163), control returns to step CSlllshowninFigure6. Accordingly, in the present embodiment of the SLR camera system, an in-focus priority control in which the shutter cannot be released unless 5 an in-focus state is obtained is adopted. A release priority control in whichth.e shutter can be released even in an out-offocus state can be adopted. In this case, the operation at step CS163 is omitted.

If it is determined at step CS163 that an in-focus 10 state has been obtained (if YES at step CS165), it is determined whether the release switch SWR is ON (step CS165). If the release switch SWR is OFF (if NO at step CS165), control returns to step CSlll.

If the release swi chSWR is ON (if YES at step CS165), 15 it is determined whether the new-type flag is 1 (step CS167). If the new-type flag is 1 (if YES at step CS167), a release stage indicator RLS is set to "1 n and information on the indicator RLS= "1" is transmitted to the lens CPU 211 (step CS169). Subsequently control 20 proceeds to step CS171. If the new-type flag is not 1 (if NO at step CS167), control skips step CS169 to proceed straight from step CS167 to step CS171, so that the information on the indicator RLS="1" is not transmitted to the lens CPU 211. The release stage indicator RLS="1" 25 informs the photographing lens 200 of a stage at which

- 39 the quick return mirror is moving toward the retracted position thereof after the release switch SWR has been turned ON.

At step CS171 the mirror circuit 123 is actuated to 5 drive a mirror drive motor so that the quick return mirror of the camera body 100 moves up to a retracted position.

Subsequently, it is determined whether the new-type flag is 1 (step CS173) . If the new-type flag is 1 (if YES at step CS173), the release stage indicator RLS is set to 10 "2", and information on the stage indicator RLS= '2 ' is transmitted to the lens CPU 211 (step CS175).

Subsequently, control proceeds to step CS177. If the new-type flag is not 1 (if NO at step CS173), control skips step CS175 to proceed straight from step CS173 to step 15 CS177, so that the information on the indicator RLS="2" is not transmitted to the lens CPU 211. The release stage indicator RLS="2" informs the photographing lens 200 of a stage at which a film frame is ready for and under exposure after the quick return mirror has moved up to 20 the retracted position thereof.

At step CS177 the shutter circuit 125 is actuated to drive the focal plane shutter mechanism to perform an exposure operation. Upon completion of the exposure operation, it is determined whether the new-type flag is 25 1 (step CS179). If the new-type flag is 1 (if YES at step

- 40 CS179), the release stage indicator RLS is set to "3", and information on this indicator RLS="3" is transmitted to the lens CPU 211 (step CS181). Subsequently control proceeds to step CS183. If the newtype flag is not 1 5 (if NO at step CS179), control skips step CS181 to proceed straight from step CS179 to step CS183, so that the information on the indicator RLS= 3n is not transmitted to the lens CPU 211. The release stage indicator RLS=" 3" informs the photographing lens 200 of a stage at which 10 film is wound after the exposure operation has been completed. At step CS183 a film winding operation in which the film- winding circuit 127 is actuated to drive a film motor (shutter charge motor) to wind film by one frame is 15 performed while a shutter charge operation is performed (step CS183). Subsequently,it is determined whether the new-type flag is "1" (step CS185). If the new-type flag is 1 (if YES at step CS185) the release stage indicator RLS is set to "0", and information on this indicator RLS= 20 "0" is transmitted to the lens CPU 211 (step CS187).

Subsequently control returns to step CS111. If the new-type flag is not 1 (if NO at step CS185) controlskips step CS187to return straight from step CS185tostepCS111, so that the information on the indicator RLS="O" is not 25 transmitted to the lens CPU 211. The release stage

: -41 indicator RLS "O" informs the photographing lens of a stage at which the aforementioned film winding operation has been completed, i.e., a state at which the shutter can again be released.

5 In the above described release process at and after step CS151, the release stage indicator RLS that indicates a stage in the release process is transmitted to the lens CPU 211 each time each stage in the release process is completed, if the (new-type) photographing 10 lens 200 is mounted to the camera body 100. This makes it possible for the photographing lens 200 to perform operations which correspondLotheoperational state and stage of the camera body 100.

The communication identification process, which is 15 composed of the oldtype communication process at step CS103 and the new-type communication setting request process at step CS105, will be hereinafter discussed in detail with reference to the flow charts shown in Figures 8A and 8B. Figure 8A shows operations of the 20 communication identification process, while Figure 8B shows operations of the photographing lens 200 which are performed by the lens CPU 211 in accordance with operations of the newtype communication setting request process at step CS105. The new-type communication 25 setting request process at step CS105 includes operations

-42 at steps CS203 through CS215 shown in Figure 8A.

Control enters the communication identification process immediately after the power of the camera body 100 is turned ON. The communication identification 5 process is performed toidentify the type of photographing lens 200 and communication protocols used therefor.

Immediately after the power of the camera body 100 is turned ON (i.e., immediately after it is determined that the main switchSWMAIN is ONatstepCS101),controlenters 10 the old-type communication process at step CS103. In the old-type communication process at step CS103, it is determined whether the photographing lens currently mounted to the camera body 100 is provided with a lens ROM from which the body CPU 111 can read out any 15 predetermined lens data, and subsequently the old-type communication (lens ROM communication) is performed in accordance with communication protocols used for the photographing lens having such a lens ROM, if it is determined that the photographing lens currently mounted 20 to the camera body 100 is provided with such a lens ROM.

In the lens ROM communication, predetermined lens data written in the lens ROM 221 are read therefrom. This lens data includes data on the lens type of the currently mounted photographing lens.

25 Upon completion of the lens ROM communication, it is

-43 determined, from the result ofthelens ROM communication, whether the photographing lens 200 currently mounted to the camera body 100 is a new type of photographing lens (step CS203). If it is determined that a new type of 5 photographing lens is not mounted to the camera body 100 (if NO at step CS203), control exits the communication identification process, and from this time on only the old-type communication (lens ROM communication) is performed between the photographing lens 200 and the 10 camera body 100.

If it is determined at step CS203 that the photographing lens 200 mounted to the camera body 100 is a new type of photographing lens (if YES at step CS203), it is determined whether the currently mounted (new 15 type) photographing lens 200 is of a type (VpzON type) which operates with power supplied from the power contact 105 (VPZ) (step CS205). If the currently mounted photographing lens 200 is a VpzON type lens (if YES at step CS205), the power contact 105 (VPZ) is turned ON; 20 namely, power is supplied to the power contact 105 (VPz) (step CS207). Subsequently, control proceeds to step CS209. On the other hand, if the currently mounted photographing lens 200 is not a VpzON type lens (if NO at step CS205), control skips step CS207 to proceed 25 straight from step CS205 tostep CS209 so that no power

-44 is supplied to the power contact 105 (VPZ).

At step CS209 the level of the fifth contact 104e (Fmaxl/ Inverse-FBL) is made to fall to a low level ("Lo" or "Lo level), and subsequently it is determined whether 5 the level of the sixth contact 104f (Fmax2/ InverseFLB) is a low level (step CS211). The operation at step CS211 is repeated as long as the level of the sixth contact 104f (Fmax2/ Inverse-FLB) is a high level. If it is determined at step CS211 that the level of the sixth contact 104f 10 (Fmax2/Inverse-FLB) isalowlevel (if YES et step CS211), the level of the fifth contact 104e (Fmaxl/ Inverse-F8L) is raised to a high level("Hi, or 'H,'level) (step CS213), and subsequently it is determined whether the level of the sixth contact 104f (Fmax2/ InverseFLB) is a high 15 level (step CS215). The operation at step CS215 is repeated as long as the level of the sixth contact 104f (Fmax2/ InverseFLB) is a low level. If it is determined at step CS215 that the level of the sixth contact 104f (Fmax2/Inverse-FLB) is ahighlevel(if YES atstepCS215), 20 this means that the (new type of) photographing lens 200 mounted to the camera body 100 operates normally, so that control comes out of the communication identification process, and from this time on new-type communication is performed between the photographing lens 200 (the lens Is CPU 211) and the camera body 100 (the body CPU 111).

-45 On the other hand, while the camera body 100 performs the operations at steps CS207 through CS215, the (new-type) photographing lens 200 performs the operations represented by the flow chart shown in Figure 5 8B. If the power contact 105 (VPZ) is supplied with power at step CS207, this power is supplied to the photographing lens 200 via the power contact 205 (VPZ). This causes the regulator 243 to supply a constant voltage to the lens CPU 211, which in turn causes the lens CPU 211 to 10 initialize internal RAM thereof (step LS201).

Subsequently, it is determined whether the level of the fifth contact 204e (Fmaxl/ Inverse-FBL) is a low level (step LS203). The operation at step LS203 is repeated as long as the level of the fifth contact 204e (Fmaxl/ 15 Inverse-FBL) is a high level. If it is determined, via the fifth contact 204e (Fmaxl/ Inverse-FBL) and the port INT of the lens CPU211,that the level of the fifth contact 104e (Fmaxl/ Inverse-FBL) falls to a low level due to the operation at step CS209 (if YES at step LS203), the level 20 of the sixth contact 204f (Fmax2/ Inverse-FLB) is made to fall to a low level via the port P00 of the lens CPU 211 (step LS205). Thereafter, it is determined whether the level of the fifth contact 204e (Fmaxl/ Inverse-FBL) is a high level (step LS207). The operation at step LS207 25 is repeated as long as the level of the fifth contact 204e

-46 (Fmaxl/ Inverse-FBL) is a low level. If it is determined that the level of the fifth contact 104e (Fmaxl/ Inverse-FBL) rises to a high level due to the operation at step CS213 (if YES at step LS207), the level of the 5 sixth contact 204f (Fmax2/ Inverse-FLB) is raised to a high level (stepLS209). Subsequently,controlcomes out of the communication identification process, and from this time on the new-type communication is performed between the (new-type) photographing lens 200 (the lens 10 CPU 211) and the camera body 100 (the body CPU 111).

Figure 18 shows a timing chart for the communication identification process that is performed between the body CPU 111 of the camera body 100 and the lens CPU 211 of the photographing lens 200. In the communication 15 identification process, the fifth contacts 104e and 204e (Fmaxl/ Inverse-FBL) and the sixth contacts 104f and 204f (Fmax2/ Inverse-FLB) are used to serve as handshake connectors/lines (see Figures l9A and 19B). Immediately after the power of the camera body 100 is turned ON, the 20 body CPU 111 makes the level of the fourth contact 204d (CONTL) rise to a high level to perform the old-type communication (lens R-OM communication) .

[OLD-TYPE COMMUNICATION (LENS ROM COMMUNICATION)]

Figure 20 shows a timing chart for the old-type 25 communication process between the camera body 100 and the

-47 photographing lens 200, i.e., between the body CPU 111 and the lens ROM 221. In the lens ROM communication, predetermined lens data written in the lens ROM 221 are read therefrom. The levels of the first contact 104a 5 (Fminl/ Inverse-SCKL), the third contact 104c (Fmin3/ RESL) and the fourth contact 104d (CONTL) of the group of communication/control contacts 104 of the camera body 100 before the commencement of the lens ROM communication are a high level, a high level and a low level, 10 respectively. The second contact 104b (Fmin2/ DATAL) before the commencement of the lens ROM communication is in a high impedance (floating) state.

The body CPU 111 makes the level of the fourth contact 104d (CONTL) rise to a high level to actuate the lens ROM 15 221 when starting the lens ROM communication.

Subsequently, after waiting a predetermined period of time necessary for the lens ROM to operate with stability, the body CPU 111 makes the level of the third contact 104c (Fmin3/ RESL) fall to a low level to change a state of 20 the lens ROM 221 from a disabled state to en enabled state.

Thereafter, if the body CPU 111 outputs a clock signal from the first contact 104a (Fminl/ Inverse-SCKL), the lens ROM 221 reads out predetermined date from an internal ROM thereof to output the predetermined data to the second 25 contact 204b (Fmin2/ DATAL), so that the body CPU 111

-48 inputs the predetermined data via the second contact 104b (Fmin2/ DATAL). The body CPU 111 makes the level of the third contact 104c (Fmin3/ RESL) rise to a high level upon having input a predetermined number of bytes of lens data.

5 Information on the lens type is included in data obtained via the above described lens ROM communication, and includes data (new-type lens bit = "1") for identification of the new-type photographing lens (i.e., a lens which can perform the new-type communication) and 10 data (VpZONCPU hit = "1") for identification of the necessity for power supply. The body CPU 111 of the camera body 100 identifies whether or not the photographing lens 200 mounted to the camera body 100 is a new type of photographing lens from such data.

15 [ NEW-TYPE COMMUNICATION]

Upon completion of the old-type communication, the body CPU 111 starts supplying power to the power contacts 105 and 205 (VPZ). Subsequently, the body CPU 111 makes the level of the fifth contact 104e (204e) (Fmaxl/ 20 Inverse-FBL) fall to a low level to interrupt the lens CPU 211, and waits for the level of the sixth contact 104f (204f) (Fmax2/ Inverse-FLB) to fall to a low level, i.e., waits for the lens CPU 211 to make the level of the sixth contact 204f (Fmax2/ Inverse-FLB) fall to a low level.

25 The fifth contact 104e (204e) (Fmaxl/ Inverse-FBL), -the

l -49 sixth contact 104f (204f) (Fmax2/ Inverse-FLB), and the second contact 104b (204b) (Fmin2/ DATAL) correspond to a first communication/control contact, a second communication/control contact and an data I/O contact, 5 respectively.

Upon the interrupt by the body CPU 111, the lens CPU 211 "wakes up" and operates normally if in the sleep mode, and initializes the internal RAM thereof. Subsequently, upon completion of the initializing operation, the lens 10 CPU 211 makes the level of the sixth contact 204f (Fmax2/ InverseFLB) fall to a low level, and waits for the level of the fifth contact 204e (104e) (Fmaxl/ Inverse-FBL) to rise to a high level.

Immediately after the level of the sixth contact 104f 15 (204f) (Fmax2/ Inverse-FLB) falls to a low level, the body CPU 111 makes the level of the fifth contact 104e (204e) (Fmaxl/ Inverse-FBL) rise to a high level, and waits for the level of the sixth contact 104f (204f) (Fmax2/ Inverse- FLB) to rise to a high level.

20 Immediately after the level of the fifth contact 204e (104e) (Fmaxl/ Inverse-FBL) rises to a high level, the lens CPU 211 makes the sixth contact 204f (104f) (Fmax2/ Inverse-FLB) rise to a high level to complete the communication identification process.

25 Upon identifying that the level of the sixth contact

-50 104f(204f)(Fmax2/Inverse-FLB) has risen to ahighlevel, the body CPU 111 completes the communication identification process.

From this time on, data and commands are transmitted 5 between the camera body 100 and the photographing lens 200 via the new-type communication.

The camera state information setting process performed at step CS113 will be hereinafter discussed in detail with reference to the flow chart shown in Figure 10 10. In the camera state information setting process, the information on the current states of specific switches and a flash charging system which is to be transmitted to the lens CPU 211 via the new-type communication is prepared. Specifically, in the present embodiment of the 15 SLR camera system, it is determined whether the autofocus system of the camera body 100 is in operation, whether an electronic flesh (strobe)is in the middle oicharging, whether a power hold timer has expired since the photometering switch SWS is turned OFF, and whether the 20 main switch SWMAIN is ON, wherein flags which indicate these states are set as state information.

In the camera state information setting process, it is determined whether the photometering switch SWS is ON (step CS301). If the photometering switch SWS is ON (if 25 YES at CS301), it is determined whether the AF switch SWAP

-51 is ON, i.e., whether the autofocus mode has been set via the AF switch SWAF (step CS303). If the AF switch SWAF is ON (if YES at step CS303), the AFON flag is set to "1" (step CS305) and subsequently control proceeds to step 5 CS309. If the AF switch SWAF is not ON (if NO at step CS303), the AFON flag is set to "0" (step CS307), and subsequently control proceeds to step CS309. If the AF switch SWAF is not ON (if NO at step CS301), the AFON flag is set to on (step CS307), and subsequently control 10 proceeds to step CS309.

At step CS309 it is determined whether the electronic flash is in the middle of charging. If the electronic flash is in the middle of charging (if YES at step CS309), a flag PAUSE is set to "1" (step CS311), and subsequently 15 control proceeds to step CS315. The flag PAUSE is set to"l" when any high power operation which requires alarge current is performed at present. The electric flash charging operation corresponds to a high power operation in the present embodiment of the SLR camera system.

20 Therefore,the flag PAUSE is set to "l"whenthe electronic flash is in the middle of charging. When the flag PAUSE is "1", the photographing lens 200 suspends all high power operations thereof. The film-winding operation and the shutter charge operation are also high power operations 25 performed in the present embodiment of the SLR camera

-52 system. At step CS315 it is determined whether the photometering switch SWS is ON. If the photometering switch SWS is ON (if YES at CS315), the power hold flag 5 PH is set to "1" (step CS321), and subsequently control proceeds to step CS323. If the photometering switch SWS is not ON (if NO at CS315), it is determined whether the power hold timer has expired (step CS317). If the power hold timer has expired (if YES at step CS317), the power 10 hold flag PH is set to "0" (step CS319), and subsequently control proceeds to step CS323. If the power hold timer has not expired (if NO at step CS317), the power hold flag PH is set to "1" (step CS321), and subsequently control proceeds to step CS323. The power hold timer measures 15 the timeitrom the moment the photometering switch SWS is turned OFF to the moment the body CPU 111 enters a sleep mode, and the power hold flag PH "1" or "0" indicates that the camera body 100 is in operation or in a sleep mode (a power saving mode)' respectively.

20 At step CS323, it is determined whether the main switch SWMAIN is ON. If the main switch SWMAIN is ON (if YES at step CS323), the SWMAIN flag is set to "1" (step CS325), and subsequently control returns. If the main switch SWMAIN is not ON (if NO at step CS323), the SWMAIN 25 flag is set tot (step Cs327), and subsequently control

-53 returns. [NEW-TYPE COMMUNICATION (LENS CPU COMMUNICATION)]

Timing charts in the new-type communication between the lens CPU 211 and the body CPU 111 are shown in Figures 5 18, 19A, 19B, 21A and 21B. In the pew-type communication, the fifth contacts 104e and 204e (Fmaxl/ InverseFBL), and the sixth contacts 104f and 204f (Fmax2/ Inverse FLB), are used to serve es handshakoconnectors/lines(see Figures l9A and l9B). The level of each of the fifth 10 contact 104e (Fmaxl/ Inverse-FBL) and the sixth contact 104f (Fmax2/ Inverse-FLB) is pulled up by the body CPU . 111 so that the fifth contact 104e (Fmaxl/ Inverse-FBL) and the sixth contact 104f (Fmax2/ Inverse-FLB) cannot short circuit when the new type of photographing lens 200 15 is mounted to or dismounted from the camera body 100 (see Figures 19A and 19B).

[NEW-TYPE COMMUNICATION SETTING REQUEST PROCESS]

The new-type communication setting request process performed at step CS105 will be hereinafter discussed in 20 detail with reference to the flow chart shown in Figure 9. In the new-type communication setting request process, firstly it is determined whether the new-type flag is "1", i.e., whether the photographing lens 200 25 currently mounted to the camera body 100 is a new type

-54 of photographing lens (step CS221). If the new-type flag is not "1" (if NO at step CS221), control returns since the currently mounted photographing lens 200 is not a new type of photographing lens. If the new-type flag is "1" 5 (if YES atstepCS221),operations at and after steps CS223 in the new-type communication setting request process are performed since the photographing lens 200 currently mounted to the camera body 100 is a new type of photographing lens 200 which allows new-type 10 communication.

At step CS223 it is determined whether the second power flag VpzONCPU is "1". If the second power flag VpzONCPU is "l" (if YES et step CS223), the power contact 105 (VPZ) is turned ON, namely, power is supplied to the 15 power contact 105 (VPZ) (step CS225). Subsequently, control proceeds to step CS227. On the other hand, if the second power flag VpzONCPU is not "1" (if NO at step CS223), control skips step CS225 to proceed straight from step CS221 to step CS225, so that no power is supplied 20 to the power contact 105 (VPZ).

At step CS227, the level of the fifth contact 104e (Fmaxl/ Inverse-FBL) is made to fall to a low level, and subsequently it is determined whether the level of the sixth contact 104f (Fmax2/ Inverse-FLB) is a low level 25 (step CS229). The operation at step CS229 is repeated

-55 as long as the level of the sixth contact 104f (Fmax2/ Inverse-FLB) is a high level. If it is determined at step CS229 that the level of the sixth contact 104f (Fmax2/ Inverse-FLB) is a low level (if YES at step CS229), the 5 level of the fifth contact 104e (Fmaxl/ Inverse-FBL) is raised to a high level (step CS231), and subsequently it is determined whether the level of the sixth contact 104f (Fmax2/ Inverse-FLB) is a high level (step CS233). The operation at step CS233 is repeated as long as the level 10 of the sixth contact 104f (Fmax2/ Inverse-FLB) is a low level. If it is determined at step CS233 that the level of the sixth contact 104f (Fmax2/ Inverse-FLB) is a high level (if YES at step CS233), control returns, i.e., control proceeds to step CS107.

15 [IMAGE-SHAKE COMPENSATION DATA SETTING PROCESS]

The image-shake compensation data setting process, which is performed at step CS137 on condition that the photographing lens 200 mounted to the camera body 100 is of a type which incorporates an image-shake compensation 20 device, will be hereinafter discussed in detail with reference to the flow-chart shown in Figure 11. Figure 12A shows various elements of a control system of an embodiment (first embodiment) of the photographing lens 200 which incorporates an image-shake compensation 25 device. Figure 12B shows a conceptual diagram of a

-56 compensation lens (an image-stabilizing optical system) LC of the image-shake compensation device. The image-shake compensation device includes a pair of sensors, i.e., an X-direction angular speed sensor 5 (horizontal-vibration sensor) 251 and a Y-direction angular speed sensor (vertical-vibration sensor) 252, for determining magnitude and direction of the vibration of the photographing lens 200 due to hand movement. If a state where the photographing lens 200 is properly 10 mounted to the camera body 100 and normally held in a horizontal position is considered as a reference state, the X-direction angular speed sensor 251 senses the angular speed of the photographing lens 200 in the horizontal direction of the optical axis thereof (in the 15 X-direction about the Y-axis), while the Y-direction angular speed sensor senses the angular speed of the photographing lens 200 in the horizontal direction of the optica' axis thereof (in the Y-direction about the X-

axis) wherein an intersection point of the optical axis 20 of the photographing lens 200 and the picture plane defines the intersection point of the X-axis and the Y-axis. Each of the vertical and horizontal vibration sensors can be a conventional gyro sensor. The vertical vibration sensor exclusively senses the shake 25 of the photographing lens 200 in the vertical direction,

-57 while the horizontal vibration sensor exclusively senses the shake of the photographing lens 200 in the horizontal direction. The image-shake compensation device of the 5 photographing lens 200 is provided with the compensation lens LC (see Figure 12B), and operates to compensate the shaking of the object image on the picture plane by driving the compensation lens LC in the X-direction and the Y-direction with an Xmotor (lens driver) 254 and a 10 Y-motor (lens driver) 257, respectively, in a plane perpendicular to the optical axis of the photographing lens 200. The position of the compensation lens LC is sensed by the number of pulses output from each of an X-direction photo-interrupter 255 and a Ydirection 15 photo-interrupter 258 when the compensation lens LC is driven, wherein a position where the optical axis of the compensation lens LC coincides with the optical axis of the photographing lens 200 is regarded as a reference position. Rotation of each of the X-motor 254 and the 20 Y-motor 257 is controlled by the lens CPU 211 via an X-motor driver253 andaY-motordriver256,respectively.

Note that the X-direction angular speed sensor 251, the Y-direction angular speed sensor 252, the X-motor driver 253, the Y-motor driver 256, the X-motor 254, the 25 Y-motor 257, X-direction photo-interrupter 255, the

-58 Y-direction photo-interrupter 258, and the compensation lens LC collectively constitute the image-shake compensation device.

The lens CPU 211 serves as a controller and an 5 arithmetic processing unit for the image-shake compensation device. The lens CPU 211 starts operating immediately after the image-shake compensation switch SW1 is turned ON to determine the direction of driving of the compensation lens LC and the amount of movement 10 (speed) thereof to drive the X-motor 254 and the Y-motor 257. In the image-shake compensation data setting process shown in Figure 11, firstly, it is determined whether the main switch flag SWMAIN has changed from "0" to '1" (step 15 CS401). If the main switch flag SWMAIN has changed from "0" to "1" (if YES at step CS401), command 70 is transmitted to the photographing lens 200 to receive data therefrom (step CS403). Subsequently, the lens CPU 211 waits for an initialize flag Init "0'' to be transmitted 20 from the camera body 100 (step CS405). Namely, it is determined at step CS405 whether the initialize flag Init is "0". Control returns to step CS403 if the initialize flag Init is not "0". The initialize flag Init is changed from "1" to "0" and output from the photographing lens 25 200 to the camera body 100 when an operation at step LS117

- -59 or LS125, in which the compensation lens LC is driven to return to the initial position thereof where the optical axis of the compensation lens coincides with the optical axis of the photographing lens 200, is completed. If it 5 is determined at step CS405 that the initialize flag Init is "0", control proceeds to step CS407. If it is determined at step CS401 that the main switch flag SWMAIN has not changed from "0" to "1" (if NO at step CS401), control proceeds straight from step CS401 to CS407.

10At step CS407, it is determined whether the main switch flag SWMAIN has changed from "1" to "0". If the main switch flag SPRAIN has changed from "1" to "0" (if YES at step CS407), this means that the main switch SWMAIN has turned from ON to OFF, so that subsequently command 1570 is transmitted to the photographinglens 200 to receive data therefrom (step CS409). Subsequently, the lens CPU 211 waits for the initialize flag Init on to be transmitted from the camera body 100 (step CS411).

Namely, it is determined at step CS411 whether the 20 initialize flag Init is "0". Control returns to step CS409 if the initialize flag Init is not "0".

If it is determined at step CS411 that the initialize flag Init is 0", control proceeds to step CS413. If it is determined at step CS407 that the main switch flag 25 SWMAIN has notchangedirom l, to o''(if NO at step CS407),

-60 control proceeds straight from step CS407 to CS413.

If it is determined at step CS413 that the power hold flag PH has changed from "l" to "0" (if YES at step CS413), command 70 is transmitted to the photographing lens 200 5 to receive data therefrom (step CS415). Subsequently, the lens CPU 211 waits for the initialize flag Init "0, to be transmitted from the camera body 100 (step CS417).

Namely, it is determined at step CS417 whether the initialize flag Init is "0". Control returns to step 10 CS415 if the initialize flag Init is not ' on. If it is determined at step CS417 that the initialize flag Init is "0", control proceeds to step CS419. If it is determined at step CS413 that the power hold flag PH has not changed from "l" to "0" (if NO at step CS413), control 15 proceeds straight from step CS413 to CS419.

At step CS419 it is determined whether the image-

shake compensation switch SW1 has been turned from ON to OFF. If the image-shake compensation switch SW1 has been turned from ON to OFF (if YES at step CS419), command D1 20 for turning OFF the image-shake compensation function of the photographing lens 200 is transmitted thereto (step CS421), and subsequently control proceeds to step CS423.

Upon receiving command D1, the photographing lens 200 completes the imageshake compensation operation. If 25 the image-shake compensation switch SW1 has not been

-61 turned from ON to OFF (if NO at step CS419), control skips CS421 to proceed straight from step CS419 to step CS423.

At step CS423 it is determined whether the image-shake compensation switch SW1 has been turned from OFF to ON.

5 If the image-shake compensation switch SW1 has been turned from OFF to ON (if YES at step CS423), command D2 for turning ON the image-shake compensation function of the photographing lens 200 is transmitted thereto (step CS425), and subsequently control returns. If the 10 image- shake compensation switch SW1 has not been turned from OFF to ON (if NO at step CS423), control skips CS425 and returns. Upon receiving command D2, the photographing lens 200 starts the image-shake compensation operation.

15 Operations and processes performed by the lens CPU 211 of the photographing lens 200 that incorporates the image-shake compensation device will be hereinafter discussedindetailwith reference to the flow charts shown in Figures 13 through 17. Figure 13 shows 20 a flow chart for the main process of the photographing lens 200 which is performed by the lens CPU 211. Control enters the main process immediately after the lens CPU 211 is supplied with power vie the operation et stepCS225, at which power is supplied to the power contact 105 (VPZ).

25 In the main process shown in Figure 13, firstly the

-62 lens CPU 211 initializes internal RAM and ports thereof (step LS101). Subsequently, a new-type communication setting process ("new-type communication setting process" shown in Figure 14) is performed (step LS103).

5 In this process, a lms-timer interrupt (see Figure 15) and an interrupt via the port (inverse) INT of the lens CPU 211 (see Figure 16) are enabled to receive aninterrupt from the camera body 100 to thereby make the new-type communication possible between the new type of 10 photographing lens (photographing lens 200) and the camera body 100.

Subsequently, it is determined whether a sleep flag which is set to ln at step LS433 or LS 437 iS "1" (step LS105). If the sleep flag is "1" (if YES at step LS105), 15 the lens CPU 211 stops (prohibits) operations of internal devices of the photographing lens 200 such as the AF motor 261, the power zoom motor 264, or the image-shake compensation motors (X-motor 254 and Y-motor 257) ( step LS107), the sleep flag is set to "0" (step LS109), and 20 the lens CPU 211 enters the sleep mode (step LSlll). The lens CPU 211 "wakes up" upon receiving an interrupt signal via the port (inverse) INT thereof.

If it is determined at step CS105 that the sleep flag is not "l" (if NO at step LS105), it is determined whether 25 a compensation lens reset flag is "1" (step LS113). If

-63 the compensation lens reset flag is "1" (if YES at step LS113),the initialize flagInit issettoUl''(stepLSl15).

Subsequently, a resetting operation is performed (step LS117). In the resetting operation, the X-motor 254 and 5 Y-motor 257 are driven to move the compensation lens LC to firstly a predetermined mechanical extremity (reference point) in the range of movement of the compensation lens LC, and subsequently the initial position (central position) thereof where the optical 10 axis of the compensation lens LC coincides with the optical axis of the photographing lens 200. After the resetting operation is performed, the compensation lens reset flag and the initialize flag are set to "O" (step LS119), and control proceeds to step LS121. According 15 to this resetting operation, the absolute position of the compensation lens LC is secured, and accordingly the compensation lens LC can be positioned precisely at the initial position (central position) thereof.

If it is determined at step LS113 that the 20 compensation lens reset flag is not"1", it is determined whether a compensation lens center flag is "1" (step LS121). If the compensation lens center flag is not "1" (if NO at step LS121), control returns to step LS105. If the compensation lens center flag is "1" (if YES at step 25 LS121),the initialize flagInit is set to"l"(stepLS123)

-64 Subsequently, a centering operation is performed in which the X-motor 254 and Y-motor 257 are driven to move the compensation lens LC to the initial position (central position) where the optical axis of the compensation lens 5 LC coincides with the optical axis of the photographing lens 200 (step LS125). Subsequently, the compensation lens center flag and the initialize flag are set to on (step LSl27), and control returns to step LS105.

The new-type communication setting process 10 performed at step LS103 will be hereinafter discussed in detail with reference to the flow chart shown in Figure 14. In the new-type communication setting process, firstly it is determined whether the level of the fifth contact 204e (Fmaxl/ Inverse-FBL) is a low level (step 15 LS221). If the level of the fifth contact 204e (Fmaxl/ Inverse-FBL) is not a low level (if NO step LS221), the operation at step LS221 is performed again, so that the operation at step LS221 is repeated until the level of the fifth contact 204e (Fmaxl/ Inverse-FBL) falls to a 20 low level. If the level of the fifth contact 204e (Fmaxl/ Inverse-FBL) is a low level (if YES step LS221) , the sixthcontact 204f (Fmax2/ Inverse-FLB) is made to fall to a low level (step LS223), and subsequently a communication setting process is performed (step LS225). The 25 communication setting process includes a setting process

-65 for serial communication, and an interrupt enabling process via the port (inverse) INT of the lens CPU 211.

Upon completion of the communication setting process at step LS225, it is determined whether the level 5 of the fifth contact 204e (Fmaxl/ InverseFBL) is a high level (step LS227). If the level of the fifth contact 204e (Fmaxl/ Inverse-FBL) is not a high level (if NO step LS227), the operation at step LS227 is performed again, so that the operation at step LS227 is repeated until the 10 levelof the fifth contact204e (Fmaxl/Inverse-FBL) rises to a high level. If the level of the fifth contact 204e (Fmaxl/ Inverse-FBL) is a high level (if YES step LS227), the sixth contact 204f (Fmax2/ Inverse-FLB) is raised to a high level (step LS229), and subsequently control 15 returns.

A lms-timer interrupt process for the image-shake compensation operation will be hereinafter discussed in detail with reference to the flow chart shown in Figure 15. The lms-timer interrupt process starts each time a 20 lms hard timer expires during operation of the lens CPU 211. In the lmstimer interrupt process, the lens CPU 211 inputs an angular speed signal from each of the X-direction angular speed sensor 251 and the Y-direction angular speed sensor 252 to detect the vibration of the 25 photographing lens 200 due to hand movement, and

-66 subsequently determines the direction of driving of the compensation lens LC and the amount of movement (speed) thereof to drive the X-motor 254 and the Y-motor 257 to move the compensation lens LC by the determined amount 5 of movement in the determined driving direction.

In the lms-timer interrupt process, firstly it is determined whether a compensation function OFF flag is 1" (step LS301). If the compensation function OFF flag is "1" (if YES step LS301), a compensation work flag is 10 set to "0" (step LS303) and control returns. The compensation work flag "1" or "0" indicates that the image-shake compensation device operates or does not operate, respectively.

If the compensation function OFF flag is "0,' (if NO 15 step LS301), it is determined whether a compensation ON flag is "0" (step LS305). If the compensation ON flag is "0"(if YES step LS305), this means that the imageshake compensation operation is not performed, so that the compensation work flag is set to "0, (step LS303), and 20 control returns.

If the compensation ON flag is "l"(if NO step LS305), the compensation work flag is set to "l", and subsequently a vibration detection process is performed (step LS309).

In the vibration detection process, the lens CPU inputs 25 an angular speed signal from each of the X-direction

-67 angularspeedsensor251 end the Y-direction angular speed sensor 252 to detect the vibration of the photographing lens 200, and subsequently determines the direction of driving of the compensation lens LC and the amount of 5 movement thereof.

After the vibration detection process at step LS309 is performed, it is determined whether a drive ON flag is "0" (step LS311). If the drive ON flag is not "0" (if NO at step LS311), the X-motor 254 and the Y-motor 257 10 are driven to move the compensation lens LC by the amount of movement in the driving direction that are determined at step LS309 (step LS315), and subsequently control returns. If the drive ON flag is "0" (if YES at step LS311), the driving of each of the X-motor 254 and 15 the Y- motor 257 is stopped forcefully (step LS313), and control returns.

An inverse-INT interrupt process will be hereinafter discussed with reference to the flow chart shown in Figures 16 and 17. The inverse-INT interrupt 20 process starts immediately after the level of the fifth contact 204e (Fmaxl/ Inverse-FBL) falls to a low level to thereby cause the port (inverse) INT of the lens CPU 211 to fall to a low level.

In the inverse-INT interrupt process, firstly at 25 least one command is received from the camera body 100

-68 via the new-type communication (step LS401).

Subsequently, it is determined whether at least one of commands 70, 71 and 72 was received at step LS401 (step LS403). If at least one of commands 70, 71 and 72 was 5 received at step LS401 (if YES at step LS403) , a lens data transmitting process (8-bit data transmitting process) is performed via the new-type communication (step LSd05), and control proceeds to step LS407. If none of commands 70, 71 and 72 was received at step LS401 (if NO at step 10 LS403), control proceeds straight from step LS403 to step LS407.

At step LS407, it is determined whether at least one of commands BO and B1 was received at step LS401. If neither of commands BO and B1 was received at step LS401 15 (if NO at step LS407), control proceeds to step LS431.

If at least one of commands BO and B1 was received at step LS401(if YES atstepLS407),abodydata receiving process is performed via the pew-type communication (step LS409).

Subsequently, it is determined whether the main switch 20 flag SWMAIN has changed from "O" to "1" (step LS411), whether the main switch flag SWMAIN has changed from "1" to "O" (step LS415), whether the power hold flag PH is "1 ' (step LS419), and whether the power hold flag PH has changed from "1'' to 0" (step LS423).

25 If it is determined at step LS411 that the main

* -69 switch flag SWMAIN has changed from "0" to "1" (if YES at step LS411), the compensation lens reset flag is set to "1" (step LS413), and control proceeds to step LS415.

If it is determined at step LS415 the main switch flag 5 SWMAIN has changed from "alto "0" (if YES at step LS415), the compensation lens center flag is set to "1" (step LS417), and control proceeds to step LS419. If it is determined at step LS419 that the power hold flag PH is "1" (if YES at step LS419), the compensation ON flag is 10 set to"l"(stepLS421),andcontrolproceedstostep LS423 If it is determined at step LS423 that the power hold flag PH has changed from "1" to "0" (if YES at step LS423), the compensation ONflagis set to"0" and the compensation lens center flag is set to "1" (step LS424), and control 15 proceeds to step LS425. If it is determined "NO" at all of steps LS411, LS415, LS419 and LS423, control proceeds from step LS411 to step LS425 with none of the operations at steps LS413, LS417, LS421 and LS424 being performed.

At step LS425, it is determined whether the flag 20 PAUSE is "1". If the flag PAUSE is "1" (if YES at step LS425), the drive ON flag is set to "0" (step LS427), and control proceeds to step LS431. If the flag PAUSE is "0" (if NO at step LS425), the drive ON flag is set to "1" (step LS429), and control proceeds to step LS431. The 25 flag PAUSE is set to "1" when any high power operation

-70 which requires a large current is currently performed.

In the present embodiment of the SLR camera system, the flag PAUSE is set to "1" when the electronic flash is in the middle of charging (step CS311) . Subsequently, the 5 lens CPU 211 sets the drive ON flag to o n upon receipt of the flag PAUSE "1" (step LS427), and control proceeds from step LS311 to step LS313 to stop the driving of each of the X-motor 254 and the Y-motor 257 forcefully in the lms-timer interrupt process shownin Figure15. However, 10 the X-direction angular speed sensor 251 and the Y direction angular speed sensor 252 continue to operate.

It is determined at step LS431 whether at least one of commands 71 and B1 was received at step LS401. If at least one of commands 71 and B1 was received at step 15 LS401 (if YES at step LS431), the sleep flag is set to "l" (step LS433), and control proceeds to step LS435. If neither of commands 71 and B1 was received at step LS401 (if NO at step LS431), control proceeds from step LS431 to step LS435. If the sleep flag is set to "1", control 20 proceeds from step LS105 to step LS107 so that the lens CPU 211 enters the sleep mode in the main process shown in Figure 13.

At step LS435, it is determined whether command DO was received at step LS401. If command DO was received 25 at step LS401 (if YES at step LS435), the sleep flag is

-71 set to"l" (stepLS437),andcontrolproceedstostepLS439.

If command D0 was not received at step LS401 (if NO at step LS435), control proceeds straight from step LS435 to step LS439.

5 At step LS439, it is determined whether command D1 was received at step LS401. If command Dl was received at step LS401 (if YES at step LS439), the compensation function OFF flag is set toll" (step LS441), and control proceeds to step LS443. If command D1 was not received 10 at step LS401 (if NO at step LS439), control proceeds straight from step LS439 to step LS443.

At step LS443 it is determined whether command D2 was received at step LS401. If command D2 was received at step LS401 (if YES at step LS443), the compensation 15 function OFF flag is set to U0" (step LS445), and control proceeds to step LS447. If command D2 was not received at step LS401 (if NO at step LS443), control proceeds straight from step LS443 to step LS447.

At step LS447, it is determined whether command 7F 20 was received at step LS401. If command 7F was received at step LS401 (if YES at step LS447), the lens CPU 211 performs a data receiving process (dummy data communicationprocess)(stepLS449), end controlreturns.

If command 7F was not received at step LS401 (if NO at 25 step LS447), control returns.

-72 Various structures and processes of an embodiment of the photographing lens 200 which incorporates an image-shake compensation device have been described above. Another embodiment (second 5 embodiment) of the photographing lens 200 which incorporates a lens AF system will be hereinafter discussed with reference to Figures 22 through 26. It should be noted that elements and processes in the second embodiment of the photographing lens 200 which 10 are similar to those in the first embodiment of the photographing lens 200 shown in Figures 12 through 17 are respectively designated by similar reference numerals and step numbers.

Figure 22 is a block diagram of various elements 15 of a communication controlsystemof a second embodiment of the photographing lens 200 which incorporates a lens AF system. The second embodiment of the photographing lens 200 is provided with an AF motor driver 261, an AF motor (lens motor) 262 and a photo-interrupter 263. The 20 lens CPU211 drives the AFmotor262 vie the AF motor driver 261 in accordance with data on the driving amount of the AF motor 262 and the driving direction thereof that is received from the body CPU 111 to move a focusing lens group Lf along the optical axis thereof to an axial 25 position thereon at which an in- focus state is obtained.

:- - ! -73 The amount of movement of the focusing lens group Lf is detected by counting the number of pulses output from the photointerrupter 263.

Figure 23 shows a flow chart for the main process of 5 the second embodiment of the photographing lens 20Q which incorporates a lens AF system. Control enters the main process immediately after the lens CPU 211 is supplied with power via the operation at step CS225, at which power is supplied to the power contact 105 (VPZ).

10 In the main process shown in Figure 23, firstly the lens CPU 211 initializes internal RAM and ports thereof (step LS101). Subsequently, the new-type communication setting process ("new-type communication setting process" shown in Figure 14) is performed (step LS103).

15 In this process, a lms-timer interrupt (see Figure 24) and an interrupt via the port (inverse) INT of the lens CPU 211 (see Figure25) areenabledto receive an interrupt from the camera body 100 to thereby make the new-type communication possible between the photographing lens 20 200 and the camera body 100.

Subsequently, it is determined whether a sleep flag which is set to "1" at step LS433 or LS437 is "1" (step LS105). If the sleep flag is "1" (if YES at step LS105), the lens CPu 211 stops internal devices of the 25 photographing lens 200 such as the AF motor 262 and the

- ^ -74 photo-interrupter 263 (step LS107), the sleep flag is set to "O" (step LS109), and the lens CPU 211 enters the sleep mode (step LS 111). The lens CPU 211 wakes up on receiving an interrupt signal via the port (inverse) INT thereof.

5 If it is determined at step LS105 that the sleep flag is not "1" (if NO at step LS105), the operation at step LS105 is repeated. The new-type communication setting process shown in Figure 14, a lms-timer interrupt process shown in Figure 24, and an inverse-INT interrupt process 10 shown in Figure 25 are performed during the time the operation at step LS105 is repeated.

The new-type communication setting process performed at step LS 10 3 Of Figure 2 3 is identical to that shown in Figure 14, and accordingly further 15 description of the new-type communication setting

process performed at step LS103 shown in Figure 23 is omitted. The lmstimer interrupt process which is repeated at regular intervals when the lens CPu 211 is in operation, 20 in the second embodiment of the photographing lens 200, will be hereinafter discussed with reference to the flow chart shown in Figure 24. This lms-timer interrupt process starts each time a lms hard timer expires during operation of the lens CPU 211 to control operation of the 25 AF motor 262.

-75 In the lms-timer interrupt process, firstly it is determined whether an AF function ON flag is "0" (step LS331). If the AF function ON flag is "0" (if YES step LS331), a lens AF process is not performed, an 5 AF work flag is set to "0" (step LS333), and control returns. The AF work flag "l" or "0" indicates that the lens AF process operates or does not operate, respectively. If the AF function ON flag is not "0" (if NO step 10 LS331), it is determined whether a drive end flag is "l" (step LS335). If the drive end flag is "l" (if YES at step LS335), this means that the driving of the AF motor 262 has been completed, so that the AF work flag is set to "0" (step LS333) and control returns.

15 If the drive end flagis not "l''(ifNOatstep LS335), it is determined whether a drive ON flag is "0" (step LS337). IfthedriveONflagis"0" (if YES at step LS337), the AF motor 262 is stopped forcefully (step LS339), and control returns.

20 If the drive ON flag is not "0" (if NO at step LS337), the AF work flag is set to "l" (step LS341), and subsequently the AF motor 262 is started (driven) (step LS343). Subsequently, it is determined whether the driving of the AF motor 262 is completed (step LS345).

25 If the driving of the AF motor 262 is completed (if YES

-76 at step LS345), the drive end flag is set to "1" (step LS347), and control returns. If the driving of the AF motor 343 has not been completed (if NO at step LS345), control returns.

5 An inverse-INT interrupt process in the second embodiment of the photographing lens 200 will be hereinafter discussed with reference to the flow chart shown in Figures 25 and 26. The inverse-INT interrupt process starts immediately after the level of the fifth 10 contact 204e (Fmaxl/ Inverse-FBL) falls to a low level to thereby cause the port (inverse) INT of the lens CPU 211 to fall to a low level.

In the inverse-INT interrupt process, firstly at least one command is received from the camera body 100 15 via the new-type communication (step LS401).

Subsequently, it is determined whether at least one of commands 70, 71 and 72 was received at step LS401 (step LS403). If at least one of commands 70, 71 and 72 was received at step LS401 (if YES at step LS403), a lens data 20 transmitting process (8-bit data transmitting process) is performed via the new-type communication, and control proceeds to step LS407. If none of commands 70, 71 and 72 was received at step LS401 (if NO at step LS403), control proceeds straight from step LS403 to step LS407.

25 At step LS407, it is determined whether at least one

! -77- of commands B0 and B1 was received at step LS401. If | neither of commands B0 and B1 was received at step LS401 (if NO at step LS407), control proceeds to step LS461.

If at least one of commands B0 and B1 was received at step 5 LS401 (if YES et step LS407), a body date receiving process is performed via the new-type communication (step LS409).

Subsequently, it is determined whether the AF ON flag is "1" (step LS451). If the AF ON flag is "1", (if YES at step LS451), the AF function ON flag is set to "1" (step 10 LS453), and control proceeds to step LS455. If the AFON flag is not "1", (if NO at step LS451), the AF function ON flag is set to "0" (step LS454), and control proceeds to step LS455.

At step LS455 it is determined whether the release 15 stage indicator RLS is "2". The release stage indicator RLS is a two-bit data which is set to "0", "1", "2" or 3, by the body CPU 111. The release stage indicator RLS "1" indicates a stage at which the quick return mirror is moving toward the retracted position thereof after the 20 release switch SWR has been turned ON. The release stage indicator RLS "2" indicates a stage at which a film frame is under exposure after the quick return mirror has moved up to the retracted position thereof. The release stage indicator RLS "3" indicates a stage at which the camera 25 body loo is in a stage at which film is advanced after

-78 the exposure operation has been completed. The release stage indicator RLS "0" indicates any other stage of the camera body 100. If the release stage indicator RLS is "2" (if YES at step LS455), this means that a film frame 5 is under exposure after the quick return mirror has moved up to the retracted position thereof, so that the drive ON flag is set to "0" (step LS457), and control proceeds to step LS461. If the release stage indicator RLS is not "2" (if NO at step LS455), the drive ON flag is set to 10 "1" (step LS459) and control proceeds to step LS461.

At step LS461, it is determined whether command B2 was received at step LS401. If command B2 was received at step LS401 (if YES at step LS461), lens driving amount data is received from the body CPU 111 (step LS463).

15 Subsequently, this received lens driving amount data is set (step LS465), and the drive end flag is set to "0,' (step LS467). Subsequently, control proceeds to step LS431. If command B2 was not received at step LS401 tif NO at step LS461), control proceeds to step LS431.

20 It is determined at step LS431 whether at least one of commands 71 and B1 was received at step LS401. If at least one of commands 71 and B1 was received at step LS401 (if YES at step LS431), the sleep flag is set to "1,' (step LS433) and control proceeds to step LS435. If neither 25 of commands 71 and B1 was received at step LS401 (if NO

-79 at step LS431), control proceeds from step LS431 to step LS435. If the sleep flag is set to "1'', control proceeds from step LS105 to step LS107, in the main process shown in Figure 13, so that the lens CPU 211 enters the sleep 5 mode.

At step LS435, it is determined whether command DO was received at step S401. If command DO was received at step LS401 (if YES at step LS435), the sleep flag is set to"l',(step LS437) end controlproceedsto step LS469.

10 If command DO was not received at step LS401 (if NO at step LS435), control proceeds straight from step LS435 to step LS469.

At step LS469, it is determined whether command D3 was received at step LS401. If command D3 was received IS at step LS401 ( if YES at step LS469) , the drive ON flag is set to "0" (step LS471), and control proceeds to step LS473. If command D3 was not received at step LS401 ( if NO at step LS469), control proceeds straight from step LS469 to step LS473.

20 At step LS473, it is determined whether command D4 was received at step LS401. If command D4 was received at step LS401 ( if YES at step LS473), the drive ON flag is set to "1" (step LS475), and control proceeds to step LS477. If command D4 was not received at step LS401 (if 25 NO at step LS473), control proceeds straight from step

-80 LS473 to step LS477.

At step LS477, it is determined whether command 7F was received at step LS401. If command 7F was received at step LS401 (if YES at step LS447), the lens CPU 211 5 performs a data receiving process (dummy data communicationprocess)(stepLS479), end control returns.

If command 7F was not received at step LS401 (if NO at step LS477), control returns.

As can be understood from the above descriptions,

10 with the present embodiments of the SLR camera system to which the present invention is applied, when the photographing lens 200 mounted to the camera body 100 is a new type of photographing lens, the camera body 100 firstly supplies the first power for driving low power 15 elements of the photographing lens 200 to drive the lens ROM 221 to input lens data, and thereafter the camera body 100 can supply the second power, the power capacity of which is substantially greater than that of the first power, to the photographing lens 200 to drive the lens 20 CPU 211 and peripheral elements thereof. This increases the degree of freedom in selection of CPUs and electronic devices which can be used for the SLR camera system. In addition, the photographing lens 200 is made to operate with a low power when the camera body 100 performs an 25 operation which requires a large current. This makes it

-81 possible to incorporate high power components such as a lens motor and an image-shake compensation device into the photographing lens 200, and accordingly makes it possible to make such high power components operate 5 properly.

In addition, even if the photographing lens 200 mounted to a conventional camera body is not a new type of photographing lens, which cannot perform the new-type communication between the camera body and the 10 photographing lens 200, at least the old-type communication (the lens ROM communication) can be performed between the camera body and the photographing lens 200 via the lens ROM 221. Therefore, the photographing lens 200 can be used as a regular 15 interchangeable lens which incorporates a lens ROM, thus maintaining compatibility with conventional camera bodies though additional functions of the photographing lens 200 such as an image-shake compensation function cannot be utilized with conventional camera bodies.

20 Furthermore, the body controller supplies the first power to the photographing lens to drive the lens memory to read out lens data therefrom when the photographing lens is mounted to the camera body, and subsequently disables the lens memory and supplies the second power 25 to the lens controller so that the body controller and

-82 the lens controller communicate with each other if the body controller determines, from the lens data read out of the lens memory, that the photographing lens includes the lens controller. Accordingly, the photographing 5 lens can incorporate not only the lens memory which operates with the first power but also the lens controller which operates with the second power. Furthermore, the degree of freedom in selection of CPUs and electronic devices which can be used for the SLR camera system is 10 increased, lens design becomes easier and a multifunction interchangeable photographing lens can be achieved

Claims

-83 CLAIMS

1. A camera system comprising:-

a photographinglens including atleast one of a lens memory, in which lens data on said photographing lens is 5 stored, and a lens controller which controls operations of said photographing lens; and a camera body including a body controller which can communicate with at least one of said lens memory and said lens controller; a first power which can be supplied to 10 said photographing lens; and a second power which can be supplied to said photographing lens; wherein said photographing lens can be mounted to, and dismounted from, said camera body; wherein said lens memory and said lens controller 15 operate with said first power and said second power, respectively, when said photographing lens is mounted to said camera body; and wherein said body controller supplies said first power to said photographinglens to drive said lens memory 20 to read out said lens data from said lens memory when said photographing lens is mounted to said camera body, and subsequently disables said lens memory and supplies said second power to said lens controller so that said body controller and said lens controller communicate with each 25 other in the case where said body controller determines,

-84 from said lens data read out of said lens memory, that said photographing lens includes said lens controller.

2. A camera system according to claim 1, wherein said camera body comprises a body communication 5 line, a first body power line and a second body power line; wherein said photographing lens comprises a lens communication line, a first lens power line and a second lens power line which are connected with said body communication line, said first body power line and said 10 second body power line, respectively, when said photographing lens is mounted to said camera body; wherein said camera body end said photographinglens communicate with each other via said body communication line and said lens communication line; 15 wherein said camera body supplies said first power to said photographing lens via said first body power line and said first lens power line; and wherein said camera body supplies said second power to said photographinglens via said second body power line 20 and said second lens power line.

3. A camera system according to claim 2.

wherein said camera body transmits a first command, for making said lens controller enter a sleep mode, to said lens controller via said body communication line and said 25 lens communication line, said lens controller entering

-85 said sleep mode upon receiv ng said first command; and wherein said camera body transmits a second command, for making said lens controller come out of said sleep mode, to said lens controller via said body communication line s and said lens communication line, said lens controller coming out of said sleep mode upon receiving said second command. 4. A camera system according to any preceding claim 2 wherein said body controller comprises a control line for 10 changing a state of said lens memory between an enabled state and a disabled state.

5 The camera system according to any preceding claim wherein a power capacity of said second power is substantially greater than a power capacity of said first 15 power.

6. A camera body to which a photographing lens can be mounted and dismounted, said photographing lens having at least one of a lens memory, in which lens data on said photographing lens is stored, and a lens 20 controller which controls operations of said photographing lens, said camera body comprising: a body controller which can communicate with least one of said lens memory and said lens controller; a first power which can be supplied to said 25 photographing lens; and

-86 a second power which can be supplied to said photographing lens; wherein said lens memory and said lens controller operate with said first power and said second power, 5 respectively, when said photographing lens is mounted to said camera body, and wherein said body controller supplies said first power to said photographinglens to drive said lens memory to read out said lens data from said lens memory when said 10 photographing lens is mounted to said camera body, and subsequently disables said lens memory and supplies said second power to said lens controller so that said body controller and said lens controller communicate with each other in the case where said body controller determines, 15 from said lens data read out of said lens memory, that said photographing lens includes said lens controller.

7. A camera body according to claim 6 further comprising a body communication line, a first body power line and a second body power line; 20 wherein said photographing lens comprises a lens communication line, a first lens power line, and a second lens power line which are connected with said body communication line, said first body power line and said second body power line, respectively, when said 25 photographing lens is mounted to said camera body; and

-87- wherein said camera body and said photographing lens communicate with each other via said body communication line and said lens communication line; wherein said camera body supplies said first power 5 to said photographing lens via said first body power line and said first lens power line; and wherein said camera body supplies said second power to said photographing lens via said second body power line and said second lens power line.

10 8. A camera body according to claim 7 wherein said camera body transmits a first command, for making said lens controller enter a sleep mode, to said lens controller via said body communication line and said lens communication line, said lens controller entering said 15 sleep mode upon receiving said first command; and wherein said camera body transmits a second command, for making said lens controller come out of said sleep mode, to said lens controller via said body communication line and said lens communication line, said lens controller coming out 20 of said sleep mode upon receiving said second command.

9. A camera body according to any one of claims 6 to 8 wherein said body controller comprises a control line for changing a state of said lens memory between an enabled state and a disabled state.

25 10. A photographing lens which can be mounted to

-88 and dismounted from a era body, said photographing lens comprising: a lens memory in which lens data on said photographing lens is stored; and a lens controller which controls operations of said 5 photographing lens; wherein said lens memory and said lens controller operate with a first power and a second power which are supplied from said camera body, respectively, when said photographing lens is mounted to said camera body; 10 wherein said lens memory is driven to output said lens data therefrom to said camera body under control of said camera body when said camera body supplies said first power to said lens memory; and wherein said lens memory is disabled, so that said 15 lens controller communicates with said camera body, when said camera body supplies said second power to said lens controller. 11. A photographing lens according to claim 10, further comprising alenscommunicationline, a first lens 20 power line, and a second lens power line which are respectively connected with associated lines of said camera body when said photographing lens is mounted to said camera body; wherein said photographing lens communicates with 25 said camera body via said lens communication line;

-89 whereinsaid photographing lens receives said first power from said camera body vie said first lens powerline; and wherein said photographing lens receives said 5 second power from said camera body via said second lens power line.

12. A photographing lens according to claim 10 or further comprising a control line for changing a state of said lens memory between en enabled state and a disabled 10 state.

13. A camera system comprising a camera body and a photographing lens which can be mounted to and dismounted from said camera body; wherein said photographing lens includes at least 15 one of a lens memory, in which lens data on said photographing lens is stored, and an electronic device; wherein said camera body includes: a body controller which can communicate with said lens memory; 20 a first power which can be supplied to said photographing lens; and a second power which can be supplied to said photographing lens, a power capacity of said second power being greater than said first power, 25 wherein said lens memory and said electronic device

- so -

operate with said first power and said second power, respectively, when said photographing lens is mounted to said camera body; wherein said body controller supplies said first 5 power to said photographinglens to drive said lens memory to read out said lens data from said lens memory when said photographing lens is mounted to said camera body; and wherein said body controller supplies said second power to said electronic device in the case where said 10 body controller determines, from said lens data read out ofsaidlens memory, that said photographinglens includes said electronic device.

i4. A camera system substantially as herein described with reference to the accompanying drawings.

15. A camera body substantially as herein described with reference to the accompanying drawings.

16. A photographing lens substantially as herein described with reference to the accompanying drawings.