JPS6169052A - Lens interchanging camera system and interchangeable lens used in this system - Google Patents

Abstract

PURPOSE:To prevent erroneous data read by arranging a data output terminal of an interchangeable lens in the leading position in the interchangeable lens setting direction and preventing a data input terminal in the camera body side from being brought into contact with another terminal in case of setting of the interchangeable lens. CONSTITUTION:A data output terminal JL1 of the interchangeable lens provided with a lens circuit consisting of a C-MOSFET is arranged in the leading position in the interchangeable lens setting direction of an arrow Z. That is, when a seat plate contacting face 5 of the interchangeable lens and a seat plate face 11 of a camera body 21 are brought into contact with each other and the interchangeable lens is rotated in the direction of the arrow Z, a seat plate claw 13 and a bayonet claw 7 are engaged with each other to lock the interchangeable lens in a prescribed position, and at this time, the terminal JL1 is slided on terminals JB5, JB4...JB1 of the seat plate face 11 in order and is stopped in the position of the data input terminal JB1. Thus, erroneous data is not transmitted to the side of the camera body 21 because the terminal JB1 is not brought into contact with the other terminals JL2-JL5 in case of lens setting.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an interchangeable lens camera system consisting of a camera body and an interchangeable lens attached to the camera body, and to an interchangeable lens used in this system.

Conventional technology From the past, JP-A-1973-/θ111! According to Publication No. 21, an interchangeable lens camera system was proposed in which power is supplied from the camera body side to a lens circuit on the interchangeable lens side, and various data specific to the interchangeable lens is sent from this lens circuit to the camera body. ing.

However, in implementing the lens interchangeable camera stem as described above, there are the following problems, as will be explained in detail later with reference to FIGS. 4 and 5. That is, in the above-mentioned interchangeable lens camera system, power supply and signal transmission are performed by a plurality of electrical terminals arranged in a line along the direction of rotation when an interchangeable lens is attached. However, because of the arrangement in a row along the rotational direction, the terminals on the interchangeable lens side temporarily come into contact with terminals other than the corresponding terminals on the camera body side during the process of attaching the interchangeable lens. At this time, the data −′ input terminal on the camera body side is
If a terminal other than the corresponding data output terminal on the interchangeable lens comes into contact with the interchangeable lens, there is a possibility that incorrect data may be read into the camera body. If this happens, the system will subsequently operate based on this incorrect data.

An object of the present invention is to solve the above-mentioned problems and provide an interchangeable lens camera system in which incorrect data is not read on the camera body during the process of attaching the interchangeable lens, and an interchangeable lens used in this system. It is in.

Means for Solving the Problems In order to achieve the above object, the present invention provides a first terminal (JL2) on the high voltage side and a second terminal (JL5) on the ground side, which are supplied with power from the camera body. ．． A lens circuit composed of a C-MOS that receives power supply from a second terminal;
A third terminal (JL4) that receives a signal from the camera body to activate this lens circuit, a fourth terminal (JL3) that receives a clock pulse from the camera body, and a clock pulse from this fourth terminal. A fifth terminal (JLI) is provided for transmitting various data specific to the interchangeable lens sequentially output in series from the lens circuit to the camera body, and the first to fifth terminals are connected to each other when the interchangeable lens rotates when the interchangeable lens is attached. are arranged in a line along the direction and the fifth
We propose an interchangeable lens in which the terminal (JLI) is provided at the foremost position in the interchangeable lens mounting direction [21], and a camera body having sixth to tenth terminals corresponding to such an interchangeable lens and its terminal arrangement. The present invention provides an interchangeable lens camera system consisting of:

Operation Since the present invention is configured as described above, the tenth terminal (JBr) on the camera body side corresponding to the fifth terminal (JLI) of the interchangeable lens, that is, the data input terminal, is connected to the interchangeable lens during the process of attaching the interchangeable lens. It comes into contact with the fifth terminal (JLI) for the first time immediately before the installation is completed, without contacting any of the terminals on the side. Therefore, even if the camera body side is configured to sequentially read data from the data output means in the camera body and data input from the 10th terminal (JBI) through the same input terminal, the At the timing of reading data from the data output means, it is possible to eliminate the possibility that an erroneous signal may be input from the tenth terminal due to incomplete attachment of the interchangeable lens.

Embodiment (See margin p below) Figure 1 is a perspective view showing the external appearance of a zoom lens to which the present invention is applied and a camera body to which this zoom lens is attached.On the zoom lens side, (1) is for setting the shooting distance. (3) is a zoom ring for focal length adjustment, and by rotating this zoom ring (3), the focal length of the lens changes, and the focal length code plate shown in Figure 3. The sliding member installed inside the code plate (FCP) slides on the code pattern.
Data corresponding to the focal length set by the zoom ring (3) is output from the lens. (5) is the surface that touches the seat plate, and there are 5 electrical signal terminals (JLI) on this surface.
~ (JL5) are provided in a row on the same circumference centered on the optical axis. (7) is a bayonet claw for attaching this zoom lens to the camera body. (9) is an aperture pin, this pin (9) is biased by a spring in the direction of arrow tz+, an aperture (not shown) is linked to this pin (9), and at the position shown, the aperture has the minimum aperture diameter. (maximum aperture value), and the aperture becomes fully open at the position (9FL) indicated by the broken line.

On the other hand, on the camera body side (21), (11) is the seat plate surface, and on this surface, the lens side terminals (JLI) to (JLI) are connected when the lens is completely attached. Terminals (JBI) to (JB6) that are electrically connected to each other are provided in a row on the same circumference with the optical axis as the center.

(13) is a seat plate type, and when the lens is attached, it engages with the bayonet claw (7) on the lens side to fix the lens to the camera body (21). Note that a locking member, which is omitted in this figure and is omitted, is provided to lock the lens attachment. (1
5) is a diaphragm control member, and when the lens is attached, the diaphragm pin (9) on the lens side comes into contact with the partial self-diameter number (15a), and therefore the position of this member (15) The aperture aperture is determined accordingly. Refinement control member (1
5) is biased by a spring in the direction of arrow 〆), but
Since it is locked at the position shown in the figure except during the exposure control operation, the diaphragm is at its maximum aperture. When the exposure control operation starts, the aperture control member is disengaged and begins to move in the four directions of the arrows.Following this, the aperture pin (9) also moves in the direction of the arrow (Z1), and the aperture is narrowed down. Then, the narrowing down control member (15
) moves, the movement of the diaphragm control member (15) is locked, and the movement of the diaphragm pin (9) which is moving following this is also locked, thereby determining the diaphragm aperture. (17) is a reflecting mirror, and the state shown in the figure is the observation position of the subject, and during the exposure operation, this reflecting mirror (17)
) rises, and the rays of light that pass through the photographic lens reach the film.

To attach the lens, insert the lens into the camera body, bring the seat plate contact surface (5) into contact with the seat plate surface (11), and rotate it in the direction of the arrow (Z). Spring member (not shown) provided at the rear of the seat plate claw (13)
At the final rotational position, the lens is fixed by a locking member (not shown) l. Here, the terminal (JB
I), (JLI) is the terminal for data transfer from the lens to the camera, (JBRI, CJLR) is from the camera to the lens? Terminals for supplying [, (J B 3 ), (JL
3) is a terminal that supplies synchronization clock pulses from the camera to the lens, (JB4) and (JL4) are terminals that transmit a chip select signal from the camera to activate the circuit in the lens lens, (JBI), ( Jl) is a common ground terminal for the camera and lens.

As is clear from Fig. 1, the mechanical interlocking relationship between the lens and the camera body is only related to aperture drive, and no mechanical means are provided to transmit information regarding the aperture from the lens to the camera body. This means that there is plenty of space for the lens, and costs can be reduced. Furthermore, there is no need to pay attention to component errors in the mechanically interlocking members that transmit aperture information during machining.

In addition, since the terminal arrangement for transmitting and receiving electrical signals is as described above, the data receiving terminal (JBI) does not come into contact with any of the terminals (JLl) to (JLi) during the process of attaching the lens. It comes into contact with the terminal (JLI) for the first time in the final installed position, that is, in the locked state. Therefore, as will be described later in Section 1, even when the lens is incompletely attached, no current will flow from other terminals to this data terminal via the circuit inside the lens. Therefore, when the microcomputer is exchanging data with blocks other than the lens, this data is not destroyed by the current flowing in from other terminals, and the correct data can be read.

FIG. 2 is a perspective view showing the appearance of the camera body (21) to which the present invention is applied, when viewed from the rear.

(22) is the release button, and this button (22)
When pushed to the first stage, the photometry switch (Sl) shown in Fig. ff13 is closed, and photometry, calculation, and display operations begin. When the release button (22) is pushed to the second step, the release switch (S) shown in Figure $3 is closed, and if the exposure control mechanism has been fully charged, the exposure control operation starts. (23) is the exposure control mechanism. This is a sliding member that sets the control mode. When set to the position (~), the aperture priority exposure time automatic control mode (hereinafter referred to as A mode) is set. When set to the (P) position, the aperture changes depending on the brightness. This is the program mode (hereinafter referred to as P mode) in which the combination of value and exposure time is determined.In P mode, the program line changes according to the focal length data fv from the lens (fv). When fvt, the mode becomes Pt mode with high-speed shutter priority, when fvt≧fv≧fvw, the mode becomes normal Pn mode, and when fvw)f'v, the mode becomes Pw mode, which prioritizes small aperture. Here, fvt is data corresponding to, for example, the focal length B□ho, and fvw is data corresponding to the 35th order.

If the slide member (23) is in the (Sl) position, the exposure time priority aperture automatic control mode (hereinafter referred to as S mode) is activated, and if it is in the (9) position, both the exposure time and aperture are controlled based on the set values. mode (hereinafter referred to as M mode).

(25) is a button that is pressed when setting the aperture value. When this button (25) is pressed, the switch (Ass) shown in Figure 3 is closed and photometry, calculation, and display operations are performed, and the Button (27).

The setting of the aperture value is changed depending on the state of the down button (28). (26) is a button that is pressed when setting the exposure time. When this button (26) is pressed, the switch (SSS) shown in Figure 3 is closed, and photometry, calculation, and display operations are performed, and the ·button('
27) *The aperture value setting is changed depending on the state of the down button (28). When the up button (27) is pushed in, the switch (UPS) shown in FIG. 3 is closed.

At this time, press the aperture setting button (2) in A mode or M mode.
5) is pushed in, the set aperture value will move towards the small aperture side.
, 5 E Changes by 7 minutes. Furthermore, when the exposure time setting button (26) is pressed in S mode or M mode, the exposure time changes to the high speed side by 7 minutes. When the down button (28) is pressed, the switch shown in Figure 3 (
DO5) is closed. At this time, if the aperture setting button (25) is pressed in A mode or M mode, the set aperture value changes by 0.5 Ev toward the open aperture side. Also, S
When the exposure time setting button (26) is pressed in mode or M mode, the exposure time changes to the low speed side by Q, 5EV. (24) is a liquid crystal display section, which displays information such as ISO sensitivity, exposure time and aperture range for control, out-of-linkage warning, and camera shake warning. Reference numeral (29) is a force-unload display window in which the photographed frame is displayed.

FIG. 3 is a circuit diagram showing the entire camera system to which the present invention is applied. (BA) is the power supply battery, and the display circuit (
DSP), shift register (SR), AND circuit (AN
o), (ANt), (ANz), NAND circuit (NAo).

Power is supplied to (NA1). Switch (SL)
(SSS) is the exposure time setting button (
Tv switch, which is closed when 26) is pushed, (
Ass) is the AV switch that opens when the aperture value setting button (25) is pressed, (UPS) is the up switch that is closed when the up button (27) is pressed, and (DO5) is the down button (28). ) presses this transistor (BTo), the microcomputer (PC) is 1lJfW,
When starting, conduction occurs and from the power line (+V),
Light metering circuit (LMC), release magnet circuit (RLM)
), aperture stop magnet circuit (APM), mirror magnet circuit (MRM), front curtain magnet circuit (ICM)
) Rear curtain magnet circuit (2cNt), aperture pulse output circuit (FEN), ISO data detection circuit (CAD),
Power is supplied to the exposure control mode data output circuit (M OD ). Furthermore, as the transistor (BTo) becomes conductive, the protective resistor (Ro), the terminal (J B2 ),
(JL2), power is supplied to the power line (VL) of the lens side circuit (LEC) surrounded by a dashed line.

Here, the protective resistor (Ro) is a resistor for preventing the terminal (JB2) from being short-circuited to the power supply terminal (+V) of the camera and the ground due to the connection made with tweezers or the like. Note that the above circuit is (LMC) and (RL8·I) as illustrated in 90~D3°TO~T3.

(APM), (MRM), (IcM), (2CM), (
FEN).

(PCI)) is configured with 0MO5. Since the circuit is composed of C-MO5 in this way, the current consumption of the circuit is small (the voltage drop due to the protective resistor (RO) is small, so even if a protective resistor is used, it is necessary to supply power to the lens circuit. There are no problems such as insufficient power supply voltage.

The operation of this camera system as a whole will be explained below based on flowcharts showing the operation of the microcomputer (PC) shown in FIGS. 6 and 7. When the microcomputer (PC) is not operating, the terminal (
P2), (P3), and (P4) are "Low". Then, the photometry switch (51), the TV switch (55)
5), when any of the AV switches (Ass) is closed, the interrupt terminal (itA) is input (blank below).
) Hag Start the operation from step 1. In step #1, set the terminal (P u) to "Low",
Make the transistor (BTo) conductive and connect the power line (+■
) and through a resistor (Re). Next, connect terminals Cp2), (p3), and (p4).
Set it to ``Hlgh'' and connect the terminal (p1
Nissl. When the terminal (p14) is set to "H1gh", the rise of this signal causes the ISO data and mode data to be latched into the shift register (SR).The ISO data output circuit (CAD) is provided on a known film container. The mode data output circuit (MO, D) is a circuit that reads the code pattern of 130 data, and the mode data output circuit (MO, D) has a sliding member that slides on the code pattern in accordance with the mode setting slide member (23) shown in FIG. Mode data corresponding to the position of the sliding member is output from the pattern. Also, when the terminal (p14) becomes @H1gh", a NAND circuit (ANo) (AN
! ) becomes active. Then, the microcomputer (PC) performs serial input/output operation in step #4, and
8 clock pulses are output from the microcontroller's internal serial input/output register 5IOR, and the data input terminal (SIN
) imports the input data. On the other hand, the shift register (SR) sequentially outputs the latched data based on the eight clock pulses input through the AND circuit (AN).
', AND circuit (ANo), NAND circuit (NA
Both outputs of FET (T) become “Low” and FET (T
o) is conductive, and the data input terminal (SIN) is “High”.
h" signal is transmitted. On the other hand, the shift register (SR
) is 1Low, the NAND circuit (NAI)
, the output of the AND circuit (ANo) is 1 “Hlgh”
As a result, the FET (T1) becomes conductive, and a "Low" signal is input to the data terminal (SIN). In addition, when the terminal (p14) of the microcomputer (PC) is “Low”, the NAND circuit (NAt) 1 ('!”Hlgh”・77
)' circuit (ANo) is "1°" and "°1・'F
Both ET (To) and (TI) become non-conductive, and the lens circuit (LEC) is connected to the data input terminal (SIN).
It is designed so that it does not have a negative effect when inputting data. When the operation of step #4 is completed, among the data taken into the serial input/output register 5IOR, the mode data is set in the register MOR, and the ISO controller (P
C) sets the terminal (px<) to "Low" and moves to step #7.

In step #7, it is determined from the ISO data taken into the serial input/output register 5IOR whether data that conforms to the regularity of the code pattern provided on the film container is read, and whether or not the data conforms to the regularity of the code pattern provided on the film container is determined. If the data is read out, the contents of the register SVR remain as they are; if the data that does not conform to the regularity is read out, a film container without a code pattern is installed, or a film container is installed. In this case, the most frequently used l50i degree decoder (for example, l5O100) is set in the register SVR.

Next, the microcomputer (1) C) shifts to the data reading operation from the lens circuit (LEC). First, set the contents of the register @On and set the terminal (pt2) to "HLgh"
``''.Here, one of the data setting registers LDRe-Le is selected according to the contents of the register, and if the contents of k is 0, then LDRG, @1'', LDRl, and ``2''. fL la LDRz, “3” oak LDR3, “4” oak LDR4, “5” then LDR&
is selected. When the terminal (pt2) becomes "Hlgh', this signal is sent to the lens circuit (LEC) via the terminals (JB4) and (JL4). This signal causes the AND circuit (ANa), (AN4), and the NAND circuit ( NAz) and decoder (DE) become active, and the reset state of the counter (COo)t (COI) is released.Then, the microcontroller performs serial input/output operation, and the terminals (JLI) and (JBI) are activated. The data from the lens is input to the data input terminal (SIN) through the clock output terminal (C: KO) and read out sequentially at the falling edge of the same clock as the clock output from the clock output terminal (C: KO), and the read data is set in the register LDRk. , adds "1" to register k. Then, determines whether the contents of the register are 16", and if it is 16", #
15, and if '6'''I is not completed, return to step #11 and read data from the next lens.

By repeating the above operations, six types of data are read into the microcomputer (PC), and registers LDRa-L
Set to DRa.

In the lens circuit, the counter (Coo) is a 3-bit counter that is output from the clock output terminal and output from the terminal (
JB3), (JL3), and an AND circuit (AN3) to count the falling edge of the clock inverted by the inverter (INo), that is, the rising edge of the clock from the clock output terminal (CKO). and decoder (DE)
In response to the output 1 from the counter (Coo), "Hlgh" signals are sequentially output from the left end to the right end terminals, and the AND circuits (ANIG) to (AN17) are sequentially activated. The AND circuit remains active from the rising edge of one clock to the rising edge of the next clock and outputs 1 bit of data.
When the counter (COO) counts the 8th tally, all outputs of OI) become "Low", and when the output of the AND circuit (AND) becomes "High", the output is output from the AND circuit (AN3). The clock that is delayed by the delay circuit (DL) is processed by the AND circuit (AN).
s) and count this falling edge.

Here, the delay circuit (DL) is provided to prevent a pulse from being output from the AND circuit (ANg) at the rise of the first clock. Therefore, the (DSL) that counts one clock every time eight clocks are input is a data selector, and the counter (
While the most significant bit of Co1) is "Low", the input data to 4 is output, and while it is "H1gh", the input data to (Bl) is output. Various types of data are fixedly stored, and an address is specified according to the address data from the data selector (DSL), and the fixedly stored data is output to the specified address, and the lower pi, f, " 6
"IN&1)?y"3°77FImt! ! (AN”°)
〜(〜”ゝ). AND circuit (AN 1
The data output from o) to (AN 1t) is output from the OR circuit (ORo), and when the output of the OR circuit (OR6) is “Hlgh”, it is 1”ET (1°z) or jjx
"High" (7) (No. 8 or terminal (J
LI), (JBI) through the data input terminal (
STN) and the output of the OR circuit (ORo) or “Lo
When the signal is "w", the FET (T3) is conductive and a "Low" signal is input to the data input terminal (SIN) via the terminals (JLI) and (JBI).

Here, it will be explained that even if the data terminal (JLI) or the lens is incompletely attached, it will not adversely affect the data transmission and reception of the camera body. Figure 4 is a circuit diagram for the case where the power terminal is at the very end and the lens is incompletely attached, and is shown for comparison with the present application, and Figure 5 shows the lens with the configuration of the present application. FIG.

Figure 4 shows that the camera's data terminal (JB2'), the power supply terminal of the interchangeable lens (JL+'), the clock terminal (JB 3") of the camera body, or the data terminal of the interchangeable lens ( JL 2').With the interchangeable lens incompletely attached, the clock is output from the clock terminal (CKO) and other data stored in the camera body is output. The output part, i.e.
Consider the case where data from a shift register (SR) is read from a data input terminal (SIN). The "High" signal of the clock is generated when the P-channel FET (T4) in the microcomputer (PC) constituted by CMO3 becomes conductive. Then, the power line (+E
) is the voltage from the FET σ4) terminal (J B 3')
, (J L 2' ) to the interchangeable lens, and the CMO5 circuit connects the interchangeable lens power line (Vt,
) is given to And this signal is connected to the terminal (JLI
), (J”) on the camera body through the data input terminal (
SIN). At this time, the data from the data output circuit (SR) inside the camera body is "Low" and the N channel FET (-1"1) is conducting, and
Assume that the W signal is in a state to be read into the data input terminal (SIN). However, if NET (rt) is conductive, the potential of the data input terminal (SIN) is the ON resistance of FET (1'+) and the diode (D2).
The ON resistance of the FET (T+) becomes a potential obtained by dividing the voltage tx (+E>), and becomes “Low” or “High”.
However, there is a possibility that incorrect data may be read into the data input terminal (SIN). If this happens, the ISO display may become strange, or
This may result in incorrect exposure.

In addition, in order to prevent the above malfunction, the terminal UB
2') and the data input terminal (SIN) or between the clock output terminal (CKO) and the terminal (JBa'), but if such a resistor is provided, A low-pass filter with a large time constant is formed by the parasitic capacitance of the data transfer line or clock transfer line and the above-mentioned resistance. For this reason, a problem arises in that it becomes impossible to exchange data at high speed.

On the other hand, in the case of the present application, the terminal (JBI) for inputting camera data is connected to the terminal (JLI) only at the final position where the interchangeable lens is attached, and when the lens is attached, other terminals (JL2) to (JL5) are connected. ) is never connected. Therefore, even if the ISO data is read through the data input terminal (SIN) with the lens incompletely attached as shown in Figure 5, there will be no negative effect on the data, and the 150 data will be correctly read by the microcontroller ( PC).

In the case of the embodiment of the present application shown in FIG.
STo), resistance (kO), terminal (JB2), (J
LI), diode (D2 power supply (VL), terminal (
Current tries to flow through JL2) and (JB3), but since the impedance has increased due to the protective resistor (kO), the lens circuit is broken and the ROM (R
The data fixedly stored in the ROM (RO) and the data fixedly stored in the ROM (RO
) and the address specification operation.

(Left below) Table 1 Table 1 shows the output of the counter (COl) and the specified ROM.
12 is a table showing the relationship between data stored at a specified address in the RO and the registers and registers set in the microcomputer (PC) for these data. Counter (GO is 11 times every 8 clock pulses input)
"Counts up. Therefore, at first the counter (Co
The output of t) is ``000''. Therefore, the data selector (DSL) outputs ``ooo'' from the input section.
The data “oooooo” is output from the ROM(RO).The check data common to all interchangeable lenses (for example, “1010101” is output from the ROM(RO).
0”) is sent to the camera body. Next, the counter (
When the output of COl) becomes 9001″, DEXEL,
The lid (DSL) receives “0000000” from the input department.
1" address data is output, and the ROM (RO) outputs the open aperture value data kVO. Here, in the case of a zoom lens whose aperture value changes depending on the focal length, the open aperture value at the shortest focal length is output. The value, that is, the data of the most open aperture value is output. When the output of the counter (COl) reaches 010'', the data selector (DSL) outputs the following:
Input section (address data from Al “00000010
'' is output, and the data Avma of the maximum aperture value (the aperture value when the aperture becomes the minimum aperture) is output from the ROM (RO).
x is output. Regarding this maximum aperture value, in the case of a zoom lens in which the aperture value changes depending on the focal length, data of the maximum aperture value at the shortest focal length is output. Counter (C
:Ox) becomes @011''', the data selector (DSL) outputs the address data of "00000011" and outputs the open photometry error data.When the output of the counter (COl) becomes 1100'', the data From the selector (DSL), ' 100 * from the input department
＊＊＊＊” address data is output.

Here, the 5-bit data indicated by "*****" is data output from the code plate (FCP) in accordance with the focal length set by the focal length setting ring (1). Data on the deviation from the aperture value at the shortest focal length (minimum focal length) is fixedly stored at this address. In addition, in the case of a zoom lens whose aperture value does not change depending on the focal length, the data ``ooooooooo'' is fixedly stored.In addition, in the case of a lens with a fixed focal length, there is no code board and a data selector is not provided. (DSL)
The address of ROhi (RO) is specified as "00000100", and the data of 'oooo oooo' is output from the ROM (RO).The output of the counter (COI) is "101". Then, the data selector (DSL) selects “1” from the input section (Bl).
01＊＊＊＊＊” data and set the focal length ring (
Data fv corresponding to the focal length set by 1)
Output. °' 0 for fixed focal length lenses
The address "0000101" is specified and fixed focal length data fv is output.

Flowchart in Figure 6 1. The main thing is the microcomputer (PC)
Explain the operation. Once the data has been captured from the lens (LEG), the light metering circuit (LM) goes to step #15.
A-D conversion is performed on the output of step C). Photometric circuit (LMC)
The output is input to the analog input terminal (ANI) and is given as a reference voltage created in the photometric circuit (LMC) or as a reference voltage to a D-A converter for A-D conversion installed in the microcontroller. Based on this reference voltage, the photometric circuit (LMC)
) is converted from analog to digital. Next, in step #x6#17, the open aperture value and maximum aperture value at the set focal length are calculated, and this data is set as A'VO and AVmaX.

In the next 1ζ, step #18, the open photometry error W included in the data obtained by A-D converting the output of the photometry circuit (LMC) is
V and the open aperture value Avo are removed based on the data read from the lens to determine the true value of Bv, and then the exposure value Ev is determined by adding the film sensitivity data set in the register SVR to this data. calculate.

Once the above operations are complete, exposure calculation begins from step #20! Move to i11 work. First, in step #20, it is determined whether the mode is P mode based on the data taken into the register MOR. If it is the P mode, the process moves to step #21, and it is determined whether the focal length data fv from the lens is larger than fVt. Then, if fv) fvt, perform the high-speed shutter priority program calculation according to step #22,
Proceed to step #35. fv in step #21
If it is determined that ≦fVt, it is determined in step #23 whether it is fv (fvw), and if it is determined that it is fv (fvw, a program calculation is performed to give priority to small aperture in step #25. Proceed to step #35.

If it is determined in step IC23 that fv≧fvw, normal program calculations are performed in step $24 and the process moves to step 35. In step #20, it is determined that the mode is not P. In step #26, it is determined whether the mode is A. In A mode, set the aperture value in register AYλ1 using buttons (25) and (2).
7) Set according to the state in (28), and after performing the calculation in step A mode in #28, proceed to step f in #35. If it is determined in step #26 that the mode is not A mode, then in step #29 it is determined whether the mode is S mode. Then, in the S mode, set the exposure time in the register T'VRI according to the state of buttons (26), (27), and (28) in step #30, and calculate the S mode in step #31. After doing so, proceed to step #35. If it is determined in step #29 that the mode is not 5 mode, in this case it is M mode, and in step #32, the aperture value corresponding to the state of buttons (25), (27), and (28) is stored in register AVRI. , button (26).

Exposure times corresponding to the states (27) and (28) are set in the register TVRl, and the M mode calculation is performed in step #34, and the process moves to step #35.

The control aperture value obtained as a result of the calculations in each of the above modes is stored in register AVR1, control exposure time 1;
Set to 2. Furthermore, overexposure warning, underexposure warning, camera shake warning, and deviation data from proper exposure in M mode are set in register DMR. In addition,
The set aperture value and exposure time are the registers AVRI and TVR.
It is set to I. In the S mode calculation, if the calculated aperture 4IiAV is Av)Avmax +c, the register AVR1Ic sets AVmaX, the TVRz sets the data of the set exposure time, and an over warning is issued. On the other hand, if Av (AVO +
Set the set exposure time data and issue an under-exposure warning. In addition, in P mode, AVmfiLX-1-Tvm
ax (When Ev, register AVR1Ic AVmaX
.

Set Tvmax in TVRz and issue an over warning.

Furthermore, when the calculated Av is Av (Avo, AV
Set O to register AVR1, and if Tv obtained by Ev-Avo=Tv or Tv≧Tvmin, then TVRz 1
The obtained Tv'' is set, and when Ty (Tvmin), Tvmin is set to TVRz and an under warning is issued.

In step #35, the number of aperture stages for control is calculated from the data of the control aperture value and the data of the open aperture value, and this data is set in the register PVR. Next, in step #36, display aperture value data Avd with a minimum unit of 0.5 Ev is calculated from the control aperture value data, and this data is set in the register AVRa. Then #
Q, 5E from control exposure time data in step 38
A transition is made to the exposure routine for display in which V is the minimum unit.

Next, this display data transfer subroutine will be explained. First, in step 0, the terminal (pl3) is set to “H”.
lgh', the AND circuit (ANt) is activated, and the display circuit (DSP) is enabled for data input.

Then, the contents of the register DMR are set in the serial input/output register 5IOR, and a serial input/output operation is performed. As a result, the contents of the register DMR are loaded into the display circuit (DSP). Next, the contents of register SVR (ISO
After setting the register 5IORI (data) and performing serial input/output operation, the aperture value display data of the register AVRs and the exposure time display data of the register TVR3 are sent to the display circuit (DSP). “Low”
” and returns to the main routine. Then, the display circuit (D
SP) outputs a signal corresponding to the read data to the segment terminal (SEG), and uses the liquid crystal display (LQ) to display a display according to the input data together with the signal from the common terminal (COM).

When the display data transfer is completed, an interrupt to the terminal (itB) is enabled in step #40. This occurs when the release switch (S2) is closed, as shown in Figure 3.
At this time, the exposure control mechanism has been fully charged and the switch (
S4) is closed, the output of the NAND circuit (NAo) goes low and an interrupt signal is input to the terminal (itB), and the microcomputer (PC)
), the exposure control operation from step #70 is performed regardless of which operation is being performed. If interrupts to the terminal (itB) are enabled, then the terminals (p2), (pa), and (p4) are set to “LOW”.
”, switches (51), (555), (A
ss)□l is closed and the input terminal (pO)
It is determined whether or not the signal is "Low". Then, if the power (pa) is "Low", proceed to step #2 and repeat the operation described above.On the other hand, if the end -F(po) is "Hlgh", proceed to step #43. and performs an operation to stop the operation of the microcomputer (PC).

First, in step #43, blank data BL is created to disable interrupts to the terminal (itB) and turn off the display.
D is set in the registers AVR3 and TvR3, the register DMR to which display data such as a rough notice is set is reset, and the process moves to the display data transfer subroutine.

After performing the above-mentioned display data transfer operation from ≦60, the terminal (p 11 ) is set to "High" and the power supply by the transistor (BTo) is stopped, and the terminal (itA
), the microcomputer (PC) stops operating. Therefore, when the microcomputer (PC) stops operating, only the ISO data is displayed on the display section (LQ).

Next, the aperture value setting subroutine shown in FIG. 7 will be explained. First, in step #101, switch (Ass)
Determine whether the is closed.

This determines whether the terminal (pO) is "Low" by setting the terminal (p4) to "Low", and
) is set to "Hlgh". If the switch (Ass) is not closed, the flag SEP is set to 0'' in step #115 and the process moves to step #116.On the other hand, if the switch (Ass) is closed, step #102 is executed. Determine whether the switch (UPS) is closed.This operation sets the terminal (pa) to "Low", determines whether the terminal (pl) is "Low", and sets the terminal (pa) to "Hlgn". This is an action that If the switch (UPS) is closed, the down switch (DO5) is
) is closed or not. This operation causes the terminal
ow", determines whether the terminal (PI) is "Low"/+), and sets the terminal (p4) to "High". Then, it is determined that the switch (DO5) is also closed. and press the up button (27 people down button)
28) are pressed in at the same time, the process directly proceeds to step #116 without changing the set value. # 103'"Switch in step (DO5
) is not closed, it is determined in step 1$104 whether the flag SEP is 1", and the flag SEP is set to "1".
If so, the up button (27) remains pressed in, so the process moves directly to step R116.

On the other hand, if the flag (SEP) is “0”, press the up button (2
7) is pushed in for the first time, the flag SEP is set to 1" in step R105, and the contents of register AVR1 (05) are added in step R106. Then, the maximum aperture value AVmaX found in step R17 and the register are The contents of AVRt are compared in step j107. If (AVRI) > Av=ax, AVmax is stored in register AVR in step R108.
Set to I and move to step R116. on the other hand,
When (AVRz)<:A'VmaX, register AV
Leave the RI(7) data as is and proceed to step R116.

If it is determined in step R102 that the switch (UPS) is not closed, the process moves to step R109 to determine whether the switch (DO3) is closed or not.
yft *J 5JIJ t b・+Lrx(-yf
-(DO5) bl; If it's not, flag SEF
is set to '0' and moves to step R116.Meanwhile,
If the switch (DO5) is closed, it is determined in step #110 whether the flag SEP is 1", and if it is 1", the down button (28) is still pressed in, so the data can be changed. The process moves to step R116 without performing.

On the other hand, if the flag SEP is 0", the down button (28
) is pushed in for the first time, and the switch (DO5) is closed. At this time, in step giii, the flag SEP is set to 1"1", and 05 is R2F from the contents of the stellar register AVRI of R112. And R11
In step 3, compare the contents of the register AVRs with the open aperture value data AVO found in step R16,
If (AVRx)>Avo, the contents of register AVRx remain unchanged and the process moves to step R116.

On the other hand, if it is (AVRl) (AVO), set the open aperture value AVO in the register AVRt in step R114.
The process moves to step 1 of 116.

In step R116, register (AVRz)
The content of is the maximum aperture value AVm found in step R17.
Determine whether it is larger than aX. If it is not larger, leave the contents of register AVRI as is; if larger, set R1.
At step 17, Avmax is set in register AVRt, and the process moves to step R118. In the step R118, it is determined whether the contents of the register AVRs are smaller than the open aperture value AVO determined in the step A16. If it is smaller, the operation of setting Avo in the register AVIζl is performed in the step R119. Main routine leaving the contents of register AVR1 as is]
I'm back. These steps R116 to R119 are performed in the register AVR before the interchangeable lens is replaced.
This is to prevent data set to + from going out of the controllable range.

Also, as shown in the subroutine above, each time the up button and down button are pressed, the
The set value changes by EV.

In addition, in the subroutine for setting the expenditure time, the step R101 is replaced with the determination of whether the switch (SSS) is open, and #to6.107.108.112.113.114
The register Av1tt of the step is TVRII(, Av
max is the shortest exposure time data rvmax, Avo
is replaced by the longest exposure time data Tvmin, and the shortest and longest exposure times do not change, so R1
Except that steps 16 to R119 are no longer necessary, the operation is exactly the same as the subroutine shown in FIG. 7, so illustration thereof is omitted.

Next, returning to FIG. 6, the operation when an interrupt signal is input to the terminal (itB) will be described. In the step of R70,
It is determined whether the refinement stage number data of the register PVR is "0". If it is not 0'', the contents of the register PVR are set to the event counter ECO, and the terminal (pc
) outputs a "Low" pulse with a time width of 1 to operate the release magnet circuit (RLM).Then, the locking of the aperture control member (15) shown in Fig. 1 is released and this member (15) moves in the direction of the arrow. It starts moving in the direction (A) and the narrowing operation begins.A pulse is generated (FEN) in response to the movement of the member (15).
) generates a pulse, and this pulse is sent to the microcomputer (PC).
4. Event counter EC input to the clock input terminal of
It is subtracted for each pulse from the stop-down stage number data preset in O. When the distance between the two ends increases, the microcomputer outputs a pulse with a certain time width to the terminal (p8) to activate the mirror magnet circuit (MR~1). As a result, the reflection mirror (17) in FIG. 1 is unlatched and the reflection mirror (17) is raised by -1. Then, a "Low" pulse is output from the terminal (p8). Lo from terminal (pc)
w" pulse and step #81, no matter what kind of interchangeable lens you use, enough time has elapsed to stop the aperture from the widest aperture to the minimum aperture, and during this time, Pulses corresponding to the number of scheduled refinement stages are generated from the encoder (FEN), and the self-response of the event counter ECO becomes 0'.
It outputs a "Low" pulse during C0 and returns to the main routine. This allows the aperture magnet circuit (<
A P M rib i operates and narrowing down control member (
15) When time T2 has elapsed, the reflection mirror (
17) has completed the rise, and “Lo” is output from the terminal (P9).
A pulse of "w" is output to start the running of the leading curtain.

When a "Low" pulse is output from the terminal (P9) and the front curtain starts running, it is set in the register TVR2 and the voltage is -1V.
C.

The time 2 based on the control exposure time data Tvc is counted, and when the counting of this time is completed, the terminal (P
ro), a "Low" pulse is output to operate the trailing curtain magnet circuit (2CM), and the trailing curtain starts running. Then, it waits until the trailing curtain completes running and the switch (S4) is released, and when the switch (S4) is released, the process moves to step 041 and performs the same operation as described in 1iii.

Since the fifth terminal, that is, the data output terminal, is placed at the earliest position in the process of attaching an interchangeable lens, the corresponding tenth terminal on the camera body side, that is, the ) data input terminal is placed at the first position in the process of attaching the interchangeable lens. Do not make contact with any of the terminals. Therefore, there is no fear that erroneous data will be read into the camera body during the process of attaching an interchangeable lens or in an incompletely attached state.

In this way, this invention achieves its purpose with an extremely simple structure of devising the terminal arrangement, and the speed of data exchange is faster than the method of providing a protective resistor on the data terminal etc. for the same purpose. There are no drawbacks such as delaying the process. Note that the sixth terminal in the present invention is high voltage,
During the process of attaching the interchangeable lens, the lens circuit will not be damaged because it will temporarily come into contact with terminals other than the first terminal on the interchangeable lens side, or it will contain a protective resistor. The circuit of the present invention is composed of CMO5, and its current consumption is small, so even if such a protective resistor is inserted, the voltage drop due to this protective resistor is small, and the power supply voltage supplied to the first terminal is sufficient. be.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing the main parts of an interchangeable lens and a camera body in a camera system according to an embodiment of the present invention, FIG. 2 is a perspective view of the camera system according to the above embodiment as seen from behind, and FIG. FIG. 4 is a circuit diagram of an embodiment, and FIG.
The figure is a circuit diagram showing the main parts of the circuit of the embodiment of the present invention for comparison with the fourth factor, FIG. 6 is a flowchart showing the operation of the circuit in FIG. 3, and FIG. 3 is a flowchart showing a subroutine. JL2, JLs...1st. 2nd terminal, RO...
Protective resistor, LEC...lens circuit, JL4...3rd
terminal, JLs...4th terminal, JLl...5th terminal,
RO...艮OM, Cot. DSL... Address designation means, Coo, DE... Serial output means, St; 555; Ass... Start signal output means, JB2. JBs...6th. 7th terminal, PI3...first active signal output means, JB4...8th terminal, CKO...clock pulse output means, JB3...9th terminal, JBI.
... 10th terminal, PI3... second active signal output means,
SR...data output means inside the camera body, PC...reading circuit, SIN...same input terminal

Claims (1)

[Scope of Claims] 1. A lens composed of a first terminal on the high voltage side that receives power from the camera body, a second terminal on the ground side, and a C-MOS that receives power from the first and second terminals. a third terminal for receiving a signal from the camera body for activating the lens circuit, a fourth terminal for receiving a clock pulse from the camera body, and a third terminal for receiving a clock pulse from the camera body; and a fifth terminal for transmitting various data specific to the interchangeable lens to the camera body, which are sequentially output in series from and the fifth terminal is provided at the foremost position in the interchangeable lens mounting direction, and the sixth to fifth terminals are respectively connected to the first to fifth terminals when the interchangeable lens is completely mounted. 10 terminals, means for outputting a power supply start signal in response to manual operation; and a power source for supplying a high voltage side voltage to the sixth terminal via a protective resistor and providing a ground level to the seventh terminal based on the start signal. , means for outputting a first active signal for activating the lens circuit to the eighth terminal;
means for outputting data to a terminal, data output means for serially outputting data within the camera body based on the clock pulse, and a second data output means for activating the data output means at a timing different from activation of the lens circuit. and a means for outputting an active signal, and based on the clock pulse, various data specific to the interchangeable lens input from the tenth terminal and data within the camera body from the data output means are input to the same input terminal. A lens-interchangeable camera system consisting of a camera body equipped with a reading circuit made up of C-MOS that sequentially reads data through a C-MOS. 2. A lens circuit consisting of a first terminal on the high voltage side that receives power from the camera body, a second terminal on the ground side, and a C-MOS that receives power from the first and second terminals. A third terminal receives a signal from the camera body to set it in an active state, a fourth terminal receives a clock pulse from the camera body, and the lens circuit sequentially outputs signals in series based on the clock pulse from this fourth terminal. a fifth terminal for transmitting various data specific to the interchangeable lens to the camera body; An interchangeable lens in which the 5 terminal is provided at the furthest position in the direction of attachment of the interchangeable lens.