JPS58172632A - Exposure controller of camera with zoom lens - Google Patents

Abstract

PURPOSE:To prevent the improper display that an aperture value shows greater one than the value of actual condition, by displaying the aperture value on the basis of aperture value data which contains no error in aperture. CONSTITUTION:An aperture controller 37 stops down a lens from a full-aperture metered value by an extent corresponding to data from a subtracting circuit 36. Therefore, actual effective aperture is free from the aperture error in AE lock mode when an AE lock switch S4 is closed and controlled to an aperture value coincident with a proper aperture value outputted from an exposure arithmetic circuit 25. A shutter controller 32 turns on an electromagnet Mg for a time based upon data from the exposure arithmetic circuit 25 to control exposure time when shutter closing operation is inhibited. Thus, when exposure is controlled on the basis of AE locking, the number of stopping-down stages is corrected to a value including the aperture error in shutter releasing to perform aperture control, so the effective aperture is controlled accurately to a calculated or setting value.

Description

[Detailed Description of the Invention] Technical Field The present invention is capable of adjusting the amount of aperture error (the difference between the calculated or set aperture value and the effective aperture value when the aperture is actually stopped down based on this aperture value) according to changes in focal length. This invention relates to an exposure control device suitable for using a variable zoom lens as a photographic lens.

BACKGROUND OF THE INVENTION In recent years, various zoom lenses with short focus and high magnification have become available on the market. In such a zoom lens, the aperture error amount generally changes from 0 to a gradually larger value as the focal length changes from the shortest focus to the long focus. In this case, it would be possible to configure the aperture mechanism so that the aperture error amount always remains O even if the focal length changes (7), but if such a measure is taken, the number of parts will increase. Inconveniences such as an increase in manufacturing costs, and a low F spec performance due to being restricted to the minimum value of the effective aperture value that changes depending on the aperture value or the focal length may occur.Therefore, the amount of aperture error may occur. There are a large number of zoom lenses (which are left to change depending on the focal length).

Problems that arise when photographing using such a zoom lens will be described below. Masu aperture 111
In the case of manual mode (hereinafter referred to as FM mode), which is controlled in response to the manual setting of both 1 and exposure time, the set aperture value is AvS, and the aperture error at the set focal length of the zoom lens is If the amount is ΔAv, the effective aperture value due to the controlled aperture diameter is Avs+ΔAv. Therefore, the aperture value at the time of shooting is ΔAv smaller than the set aperture value.
For example, if the photographer sets the aperture value and exposure time by reading the readings from a light meter that operates independently of the camera, the aperture will be underexposed. [7 mau. Next, in the case of aperture priority exposure time automatic control mode (hereinafter referred to as A priority mode) in which the exposure time is automatically controlled according to the manually set aperture value, the maximum aperture value is Avo, and the subject brightness is Bv.
Then, the photometric output from TTL aperture metering includes data ΔAv regarding the aperture error amount according to the focal length, and becomes Bv-(Avo+ΔAv).If the film sensitivity is Sv, then from this photometric output, Bv-(Avo+ΔAv) + Avo 15v-Av
The calculation s=Tv-ΔAv ・=(1) is performed, and the aperture value at the time of shooting is set to Avs→-ΔA■, which is smaller than the set aperture value Avs by ΔAv, and the exposure time remains unchanged at Tv-
It is controlled by ΔAv. In this case, the exposure is controlled to be appropriate, but the aperture value is ΔAv smaller than the set value, and the exposure time is correspondingly longer, so there is a problem that the performance is increased, which can cause camera shake6. Next, in the case of the road time priority automatic aperture control mode, in which the aperture is automatically controlled according to the manually set exposure time (hereinafter referred to as 'r priority mode), the metering output is the same as in A priority mode. By −(Avo+ΔAv), and from this photometric output, Bv−(Avo+ΔAv)×Avo−)−8v−Tvs
=Av-ΔAv-(2) Itching is performed. In this case, during aperture control, the term ΔAv cancels out, and the aperture value becomes Av and the exposure time becomes Tvs, and the a-output is controlled with the same aperture value and exposure time as when the aperture error amount is 0.
There is a problem that an aperture value that is ΔAv more open than the controlled aperture value is displayed as the controlled aperture value, resulting in E7 error. Furthermore, in the program mode where the combination of aperture value and exposure time is predetermined for each exposure value Ev and both are automatically controlled (hereinafter referred to as ≠ mode), the following calculation is performed, Aperture value is Av + (1-p)・ΔA
v (however, 1.o<p<i), the exposure time is Tv-(1-'
p)・ΔAv d is controlled. In this case as well, the aperture value is controlled to ensure proper extension, but the displayed aperture value is a value that is more open by p・ΔAv than the aperture value that would be controlled if the aperture error amount was O, and the controlled exposure time Since the length is also increased by (1-'p)·ΔAv, there is a problem that camera shake is likely to occur.

Purpose This invention solves various problems in the above-mentioned various shooting modes caused by the amount of aperture error depending on the set focal length of a zoom lens. The purpose of the present invention is to propose an exposure control device for a camera in which the aperture is controlled based on the following.

・Summary This invention provides an aperture value output device that outputs data related to a calculated or set controlled aperture value, and a data output device that outputs data related to an aperture error amount corresponding to the focal length of a zoom lens. The aperture aperture is controlled based on the aperture error amount data from this data output device and the aperture value data to be controlled from the -1U aperture value output device, and the effective aperture value is adjusted to the above aperture value data. Adjust the aperture error amount data I7 to obtain the corresponding value.
Based on this, it is independent of the amount of aperture error included in the photometric output (
This is the calculation of control data for the exposure factor r (for example, aperture value).
It is characterized by the fact that it is designed to be

Embodiment Fig. 1 is a circuit diagram for reading and outputting information from a camera accessory such as a zoom lens in order to carry out the present invention, and Fig. 3 is a circuit diagram for outputting information from an interchangeable lens attached to the camera body. It is a circuit diagram. In addition, in the following explanation, camera accessories (hereinafter simply referred to as accessories)
are broadly divided into interchangeable lenses and lens adapters. Interchangeable lenses are a general term for zoom lenses with variable focal lengths and fixed general lenses, and lens adapters are so-called lens accessories such as intermediate rings and bellows. say.

In Figure 1, (HA) is a power supply battery, and (Sl)
is a photometric switch that is opened by interlocking with the photometric button (not shown) (7). When this optical switch (Sl) is closed, the transistor (B r 1 ) conducts and the power supply battery (BA
), power is supplied to a power-on reset circuit (1), an exposure control section (FIG. 4), etc., which will be described later, via a power supply line (+V). Further, the counters, flip-flops, registers, decoders, etc. shown in the figure are constantly supplied with power from a power supply battery (BA) via a power supply line (+-E). Also, when power supply starts from the power supply line (+V), a power-on reset signal (FOR) is output from the power-on reset circuit (1), and the flip-flop (FFl)
Register (1 also I=: G 2 ) ~ (l (, l shi G13) is reset and D free knob flop (1)
Fl) and branch unit (1) I l ) are reset.

Furthermore, when the photometric switch (81) is closed, the output of the inverter (IN 1 ) becomes "High",
The next clock pulse (C) from the oscillator (PC)
1) Flip-flop (DPI) with V-1 of 1')
The Q output of becomes High ``, and the AND circuit (AN
The gate of I) is opened and a clock pulse (cp) is sent from the AND circuit (ANI) to the divider (1) II).

At the same time, this “High” signal is connected to the one-shot circuit (O8
A "High" pulse is also output from the one-shot circuit (O8+) to the one-shot circuit (O8+). This pulse is passed through an OR circuit (ORI) and flips to a 70-tube (PI).
This pulse sets the flip-flop (FPl) and makes the Q output "High".

At this time, the flip-flop (FFIO) is reset by the signal (also poi) from the power-on reset circuit (1), so its Q output is "High", and the output of the AND circuit (A N 40) is It becomes “High”. This signal is sent to the inside of the camera body and accessories to start the reading operation.
It becomes starQ.

When this start signal (Start) is output, the gate of the AND circuit (ANz) is opened and the counter (COI
).

(CO2) is released from the reset state, and the decoder (DEI) becomes ready for output. Counter (C
Ol) counts clock pulses (CP) from the oscillator CPO sent via the AND circuit (AN2), and the decoder (DEl) outputs output terminals (TBO) to (TB?) according to the output of the counter (COt). ) one of “
Table 1 shows the relationship between the input and output of this decoder (DEI).

Table 1 In Diagram 2, terminals (JA t ), (JA2)
, (JA3), (JA4).

(JAs) are terminals on the camera body side (JI3+)
, (JBz).

Connected to (JBz), (JA4), (JA5),
(JAI) receives power from the electric gap line (+li', ), (JA2) receives the clock pulse (cp), and (JA3) receives the read start signal +T'T (star).
t) is input, (JA4) is the ground terminal, (JAs)
is a terminal that outputs data to the camera body. Note that the terminals (JL+) to (JA5) of the interchangeable lens in Figure 3 are the second terminals.
End f (JAI) ~ (JAS) of the lens accessory in the diagram
This is a terminal that is connected to the camera body in the same way as . When the reading start signal (start) is input from the terminal (JBz) of the camera body through terminals r (JA3) and (JA3) (7), the counters (CO3) and (CO4) are input at the second stage.
, 2) The reset state of the flip-flop (I23) is released and the output of the decoder (DE+) and ROM (Rot) is possible. At the same time, this signal (S
tart) is also applied to the one-shot circuit (OS 4 ), and the flip-flops (FF 2 ) and (FF3) are reset by the pulse from the one-shot circuit (084). Similarly, in Figure 3, the counter (CO
s), (CO6), (CUT).

The reset state of D flip-70 tubes (DFs), (1) F6) is released, and the decoder (DE4) and l (OM(
)(02) can be output. Furthermore, the pulse from the one-shot circuit (O85) causes the flip-flop (FF
4), (FF5), and (FFs) are reset. Second
Counter (CO3) in the figure, decoder (f) ) 43) and counter (cos) in the figure $3, decoder (1) No. 1 4)
are the counter (COI) and decoder (L)El) in Figure 1.
It has the same configuration as the decoder (LiF2).

(DE4) respective output terminals (TAo) ~, (TA
7), (TLo) ~ ('r, L7) to i;! De:+
Pulses are output from the output terminals (TBo) to (TB7) of the camera (DB+) at the same timing, respectively, to synchronize the camera body and the accessory side.

(hereinafter referred to as T) Table 2-1 Example Table 2-2 Table 3 Table 2-1.2-2 shows the relationship between addresses and the contents of various data in the ROM in which various data of accessories are stored. , Table 3 shows the relationship between coded data and the content indicated by the data. The operation will be explained below based on Tables 2-1, 2-2 and 3. In Figure 2, when the read start signal (st=・r) is output, the one-shot circuit (084) is activated and the flip-flop (1"F'2) is reset, so the D flip・Even if the reset state of the flop (DF3) is released, its Q output remains “High” and the switch circuit (ASI) remains conductive.Also, in Figure 83, the D flip-flop (IJ
The Q output of Fs) remains "Low" and the switch circuit (As2) remains non-conductive. Therefore, first of all, data from the lens accessory can be transmitted to the camera body.

First, the output of the counter (CO4) becomes '01°' due to the pulse of (TAI) from the decoder (DE3), and )LOM
(RO+) (7) 7 As tress”0000001
” is given, the code for checking the lens accessory or the stored address is specified, and H, OM (
ltOr ) outputs data '11100'. Then, the flip-flop (FF3) has a terminal (TAI) set to “High” by the AND circuit (AN23).
It is set at the falling edge of the clock pulse (cp) output during
) is reset at the rising edge of the clock pulse (cp) output during "'High h". Therefore, the Q output of the flip-flop (FF3) is from the falling point of the clock pulse when the terminal (TAI) is "high" to the falling point of the clock pulse when the terminal (TA 2) is "lligh". During this period, the clock pulse (UP) goes high, that is, the terminal (TA
2) Data from ROhl (R'01) is fetched in parallel into the shift register (SR2) when the signal goes high. Thereafter, in synchronization with the rising edge of the clock pulse (C)') applied to the terminal (CL), the above data is sequentially output in series from the upper bit as described below, and the switch circuit (As 1 ) , terminal (JA
s )'+ (,, y Bs ,) to the shift register (Sf(, 1) in Fig. 1. Here, the shift register C8H, 1) is synchronized with the falling edge of the clock pulse. data from the terminal (JB5) one bit at a time). The data sent is 5 bits,
(TA3.) is read one bit at a time from the rising edge of the clock pulse, and one bit from the falling timing of the clock pulse while (TB3) is "High" is read into the shift register (il) one by one. (TB?)
Reading of one data is completed at the falling edge of the clock pulse while TBO is “High”, and at the timing of the rising edge of the next terminal (TBO), the shift register (81%1>
The output data of is latched in parallel in the register (REGl).

The decoder (1) R2) on the camera body side has the relationship between human power and output shown in Table 4.

(Left space below) Table 4 Here, the counter (CO2) whose output is given by the human power of the decoder (DB2) and (7) counts one by one at the rising edge of the terminal (TB7). )3
At the time when the first data, that is, the check data is latched into the register (REGt) at the rising edge of signal o), the terminal (do) of the decoder (DE2) is at "High". Therefore, the rising signal of the terminal (TB+) is given to the terminal of the register (f(EG2)) via the AND circuit (AN3), and the data from the register (REG t) is input to the register (C). ) is latched. Output i of this register tlmoEG2);
J 771' circuit (AN 15) Niyo"'C" 1
1100", and if the lens accessor J- is attached and the reading is "11100", an AND circuit (AN
+s) output is “High”, lens accessory -
When it is not installed, it becomes “Low”. The output of this AND circuit (AN15) is given to a display section (not shown) that displays whether or not a lens accessory is attached.

In Fig. 2, the terminal (TAL) rises next, the output of the counter (CO4) becomes "10", and the node (, [(0])
The address "0000010" is specified. Then, the ROM()to+) outputs data indicating the type of lens accessory, as shown in Table 2-1. As shown in Table 3, this data is predefined as "00001" for the automatic diaphragm interlocking type bellows and '00010' for the automatic iris interlocking type reverse adapter.This data is also defined as (7 Te terminal (THo)
is latched to the register (1 [G 1 ) of the camera body at the timing when the signal becomes “High”, and at this time, the output of the counter (CO2) becomes “0010”, and as shown in Table 4, the output from the decoder (DB2) terminal (dl) is “Hi”
gh'', register (l(, EG 3)
The data from the register (REGt) is latched.

Also, in Fig. 2, the output of the counter (CO4) is “1”.
Since it became 0pa, “ from the one-shot circuit (083)
A high "" pulse is output and the flip-flop (
FF2) is set. Then, the terminal (TAo)
At the point when the level rises to “High” (at this time, the sending of the lens accessory type data is completed), 1) Flip-flop (1) β3)
Take in the Q output of the flop (FF2) and convert the Q output to “
1. When set to ``Low'', the switch circuit (As + ) is made non-conductive so that no data is sent from the lens accessory.

The counter (COe) in Figure 3 is also the counter (C
Similarly to O4), the rising edge of the terminal (TI・1) is counted, and when the count output reaches "010", the output of the AND circuit (AN25) goes "High" and the one-shot circuit (O86) outputs "f( i g h" pulse is output and the flip 70 knob (FF4) is set. Then, the D flip 70 knob (DF3) in Figure 2 is set.
Similarly, the Q output of the D flip-flop (DFs) becomes "High" at the rising edge of the terminal (TLO), and the switch circuit (As 2 ) is connected to 45 terminals 17, making it possible to send data from the interchangeable lens. becomes 1, then the output of the counter (COs) becomes “0” at the next rising edge of the terminal (TLt).
It becomes 11'. The 3-bit output from this counter (C(,)a) is given to the lower 3 bits of the (β1) input of the multiplexer (MP2). At this time, the Q output of the D flip-flop (DFG) is still “Low”, so the multiplexer (MP 2 ) outputs data “0000011” from (β1), and this data is sent to fL OM (ELO2). This becomes the address signal. As shown in Table 2-1, check data “11100” is output from ROM (f(,02)), and the register (REO4) in Figure 1 is output in the same manner as described below.
is loaded into. In addition, the AND circuit (AN 2
8), (AN 29), OR circuit (oi Shichifuku), flip 70 tube (FF6), shift register (Saa
) are the circuits (AN 23 ) and (A
N2a), (OR3).

The circuit is similar to (FF3) and (SR2).

The data read into the register (REG4) is determined by the AND circuit (AN+a) whether it is "11100" or not. If it is determined that it is not "11100", it means that the interchangeable lens is not attached. The output of the AND circuit (A N +e) becomes "High", the gate of (AN+7) is opened, and a pulse from the terminal (TB2) or a read end signal (endl) is output. Every time the pin (TLI) rises to “High”, the output of the counter (C06) changes to “100”, “101”, °“
110'', 111''', multiplexer (1M
P2) is 0000100"', "0000101
”, “0000110”, “0000111”: 1' address data are output sequentially. Here, Table 2-1
As shown in the above address of ROM (1-t02), the maximum aperture value Avo and minimum aperture value Avmax of the interchangeable lens are stored in the above address of ROM (1-t02).
, the focal length on the wide side, and the focal length on the 'l'ele side are stored. To explain specifically using Table 3, the aperture value data is Fl, 2 to 0.5E.
A typical aperture value increasing with a pitch of v, i.e. Fl, 2~
Up to F32 is defined as "ooooo" to "10011", which does not correspond to the aperture value of the above 0.5Ev pitch, and is often [
7, the open aperture value of the lens and the aperture value F1, which exists in 17.
8 to F6.9 are defined as "10100" to "11110".

Further, the focal length data is classified into commonly used focal lengths from 88 or less to 1000ax or more as shown in Table 3, and data from "ooooo" to "11110" is defined. (7) In the case of a zoom lens, the focal length data is stored in the address "0000110".
The shortest focal length data on the e side is stored at the address "0000111", and the longest focal length data on the Te1e side is stored. On the other hand, for fixed focal length interchangeable lenses, “00
The above focal length data is stored as is at the address ``00110'', and the data ``11111'' indicating a fixed focal length is stored at the address ``0000111''. Therefore, -1 from the multiplexer (MP2) is stored. -Address data “0000100°”～°“
By sequentially outputting "0000111", the maximum aperture value, minimum aperture value, wide side focal length, and "rel" of the interchangeable lens are output.
The focal length data on the e side is stored in the register on the camera body side (
REC)5), (RECh).

(REG7) and (R,1!I08) are read sequentially. Also, the AND circuit (ANtg) determines whether the data on the Te1e side or the output of the register (REGa) to be read is "11111".
When the focal length of the interchangeable lens is fixed, the output of the AND circuit (ANtg) becomes "Ilight'". stop,
Therefore, the D flip flop (1) I=” 2 ) is the terminal (TB 2 ) of the decoder (DEI) when the terminal (C6) of the decoder (DE2) is “[high”].
) takes in the D input (that is, the output of the AND circuit (ANtg)).6 In Figure 3, the output of the counter (COa) is “111
”, the output of the AND circuit (AN26) becomes “[lig
from the one-shot circuit (O8?) to “h”.
A high level pulse is output. This pulse sets the flip-flop (F, F6) and the next terminal (TLO) rises, causing the D flip-flop (F, F6) to rise.
1) Q output of F6) becomes "High". As a result, the gate of the AND circuit (AN27) is opened and the pulse from the terminal (TLI) is input to the counter (CO7), and the multiplexer (MP2)
From (R2), the data from the input is output.

D flip-flop (I) F6) Q) Q output is “Hi”
gh” and is input from the next terminal (TL 1 ) to the Nokuru Scada counter (CO7), the counter (
The output of CO7) becomes “001”, and the output of multiplayer 4 (
MP1) and the like are output from block (10) to (C1) manually. This pro nk(1)
0) corresponds to the amount of deviation (movement) of the distance ring as a distance adjustment member of the interchangeable lens from the ■ position.1. The data will be output. This data is designed to output 4-bit data starting from "0000" no matter what kind of interchangeable lens it is. [2] Multiplexer (
This data is stored in the lower 4 bits of the input (R2) of f'vlP2), and the counter (CO2) is stored in the upper 3 bits.
Since the output of the multiplexer (MP2
), one address data from “0010000°” to “0011111” is output and this is stored in the ROM (
ROz). ROM (ROz) address “
As shown in Table 2-1, the area 0010000" to "0011111" (7) stores data on the photographing distance according to the amount of deviation of the distance adjustment member of the interchangeable lens from the position (a). Therefore, , this data is read into the registers (REGs) of the main body.

Next, when the output of the counter (COW) becomes "010", the multiplexer (MP!) outputs the data input to (α2) from block (11). This block (11) outputs data corresponding to the number of aperture stages from the open aperture position of the aperture ring as an aperture setting member of the interchangeable lens. This data is also output as 4-bit data starting with "oooo" no matter what type of interchangeable lens you use. In addition, if it is an interchangeable lens with a fixed aperture (for example, a reflective telephoto type lens), "oo"
Only the data of “oo” is output.The multiplexer (
MP2) Garara "0100000" ~ "0101111
” ノuch (7) 1 t 0) Te = 1 is output and this data is input to I(OM(ROz)) “0101111
As shown in Table 2-1, the area number "" stores data on the aperture value corresponding to the number of stops from the open aperture value of the aperture ring of the interchangeable lens.

Therefore, the set aperture value data output from the ROM (ROz) is read into the register (REG lo ) of the camera body.

In Figure 1, when the set aperture value data is read into the register (BE Gro), if the Q output of the D flip 70 knob (DF2) is "High",
In other words, if it is determined that the attached interchangeable lens is a lens with a fixed focal length,
20) is opened and a pulse from the terminal (Tl: +2) is output as a reading end signal (end2),
The reading operation ends. This is because all the data read thereafter is data to be sent to the zoom lens, so there is no need to read it in the case of a fixed focal length lens.

In Fig. 3, the output of the counter (COT) is “011”.
” from the multiplexer (MPI) to (α3
) is output from block (12). This block (12) outputs the deviation of the focal length adjustment member of the zoom lens from the focal length position on the wide side. Bit data is output. The multiplexer (+WP2) outputs one of the data from "'0110000" to ",0111111" from (β2), and this data is
z) input salel. )tOM (fLOz) (7)7
As shown in Table 2-2, data on the focal length setting according to the position of the focal length adjustment member is stored in the area from 1' response "0110000" to "0111111".
This data is output from 1 (IJluj (l(02)) and read into the register (REG r 1) on the camera body side.

Next, when the output of the counter (COT) reaches "100", the multiplexer (MPI) also outputs the data from (α3), and the ROM (ROz) is
One piece of data from "1000000" to "1001111" is entered manually. This "1000000" ~ "1"
001111'' (7) As shown in Table 2-2, the address area of the ROM (ROz) stores data ΔAv of the aperture error amount due to changes in the focal length of the zoom lens, and this data is stored in the ROM (ROz). ROz) and read into the register (REGs2) of the camera body.

Next, when the output of the counter (COT) becomes '101'', the data from the block (12) from (α3) is output from the multiplexer (MPt)) tOM(
R02) “1010000” to “1011111”
One of the data is input. This f(OM
(The area of i(02) is the set focal length f of the zoom lens.
To what extent (
Data indicating how many percent (% from f min) the value is on the long focal point side is stored. To explain this data in more detail, this data has an area of 1 (“00001”) when the value of f −/min is between 0 and 19%, and a region of 1 (“00001”) when it is between 20 and 39%. area, 3 (“00100”) if it is 40-59%
area, 4 (“01000
”) area, 5 (“100%”) if it is 80-100%
This data indicates that the area is 00'').

The register (REGta) on the main body side shown in Figure 1
) is read in the data indicating the above area, and at the same time, a read end signal (en
d3) is output, and the read end signal (end) is output from the OR circuit (Of(,3).This end signal (
end) through the OR circuit (01(2) [7 to flip
The signal is sent to the flop (FPI), and this flip-flop (FPI) is reset. Therefore, the AND circuit (A
The output terminal (start) of NA, , ) becomes “Low”, and the counters (COa), (CO2), and D flip
The flop (1) F2) enters a reset state, and the decoder (L) El) also becomes unable to output a timing signal.

Similarly, the counters (CO3), (COa), D in FIG.
The flip 70 tube (L) F3) enters a reset state, and the decoder (1) E3) and ROM (ROl) become unable to output.

Furthermore, the counters (COs) and (COa) in FIG.

(CO7), D flip 70 tube (DF5), (
DF6) enters the reset state, and the decoder (DE4)
f(OM(RO2)) becomes unable to output. As described above, the reading operation comes to an end.

In Figure 1, the photometry switch (
When Sl) remains closed, the Q output of the D flip-flop (DFl) remains "High", so the clock pulse (CP) is output via the AND circuit (ANI). continues to be input to the frequency divider (DI 1 ), and a clock pulse of, for example, 4 Hz is output from this frequency divider (DII). At the rising edge of this 4 Hz clock pulse, the one-shot circuit (O82) outputs “High”.
The pulse of "h" is output and input to the flip-flop (FFI) via the OR circuit (ORt), and the flip-flop (FFI) is set again, and its Q output becomes "High" and the AND circuit The output terminal of (AN 40) becomes ``High'' and the reading start signal (5t'2r
t) is output. Therefore, if the photometry switch (81) remains closed, data from the lens accessory-1 interchangeable lens will be read repeatedly at a cycle of 4 Hz.

Also, as will be described later in Fig. 4, when the release signal (RL) for starting the exposure control operation is output, the flip 70 knob (FFlO) in Fig. 1 is set and the Q output becomes "Low". Become. This results in an AND circuit (AN40
) is closed, and from then on the flip-flop (
Even if FF l) is set, the AND circuit (A N 40
) remains "LOW" and the information reading operation is not started. Then, when the exposed side @operation end signal (CM) in Fig. 4 is input, the OR circuit (O
The flip-flops (F, F+o) are reset again via RIO), and the output (start) of the AND circuit (AN' 40 ) becomes High'' to restart the read operation.

Incidentally, the shift register (SR2) in FIGS. 2 and 3.

(As the configuration of (81(,3)), (TA7.), (TL7.
) is High'“, t(, OM (ROI
), (RO2) data are taken in parallel,
When the data is sequentially output one bit at a time to the camera body from the timing of the next rise of (TAo) (TLO), the specific configuration of this shift register is as follows. That is, each bit is provided with a flip-flop to which the data of each bit input in parallel is preset, and the output terminal of the flip-flop corresponding to the lower bit is connected to the bit immediately above the corresponding bit. It is connected to the input terminal of the corresponding flip/70-tub, and the data preset in each 7-lip/70-tub is transferred from the lower bit to the upper bit in synchronization with the clock pulse to :11.

Furthermore, if another flip-flop is provided separately from these flip-flops, and the input terminal of this flip-flop is connected to the output terminal of the flip-flop corresponding to the most significant bit, the output from this separately provided flip-flop is The captured data is output bit by bit with a delay of one crotter pulse.

FIG. 4 is a block diagram showing an exposure control section on the camera body side that performs exposure control based on data corresponding to the aperture error amount read into the reading section on the camera body side shown in FIG. 1. (PD) is, for example, a T that is placed near the film surface and measures the intensity of the subject light that has passed through the photographic lens.
A photodetector for TL photometry, (15) is the photodetector (PD)
(16) is an A-D conversion circuit that converts the analog signal from the photometry circuit (15) into a digital signal. The photometric output from this circuit (16) includes the aperture error amount ΔAv of the zoom lens as the photographing lens, and is expressed as Bv-ΔAv-Avo. (
17) is a decoder that converts the open aperture value data from the register (REG5) in FIG. ) by adding the input data from (Bv-ΔAv-Avo) +Avo = Bv-
Calculate ΔAv. (19) is a decoder that converts the data corresponding to the aperture error amount from the register (R, ED 12) in Figure 1 into data ΔAv for calculation, and the converted data ΔAv and the data from the adder circuit (18) are The addition circuit (20) calculates (By-ΔAv)+ΔAv=Bv based on the data (Hv-ΔAy), and the data corresponding to the aperture error amount is canceled out.(21)
) is a data output circuit that outputs data Sv corresponding to the film sensitivity set by a film sensitivity setting member (not shown) provided on the camera body side;
22), the data Sv from this data output circuit (21)
and Bv based on the data By from the adder circuit (20).
The calculation +Sv = Ev is performed. An appropriate exposure value Ev that is not affected by the aperture error amount calculated in this way is input to the exposure calculation circuit (25). Note that if the photographing lens is not a zoom lens but a fixed focal length lens, the aperture error amount of the lens is 0, so the A-D conversion circuit (16)
The photometric output from the decoder (19) is (Bv-Avo), and since the register (Rm 12 ) in Figure 1 remains reset by the power-on reset signal (FOR), the aperture error is detected from the decoder (19). Data with an amount of O is output.

(23) is a decoder that converts the set aperture value data from the register (WE G 1o) in FIG. 1 into calculation data Avs, and (24) is an exposure time setting member (not shown) provided on the camera body side. The exposure calculation circuit (25) is a data output circuit that outputs data Tvs corresponding to the exposure time set by
v, open aperture value AVO from the decoder (17), set aperture value Avs1 from the decoder (23) data output circuit (
24) and a mode designation signal from an exposure calculation mode setting device (39) to be described later. This mode setting device (39) has output terminals (A) corresponding to four types of exposure control modes, respectively.
), (P), and M are connected to the exposure calculation circuit (25), and any one corresponding to the set mode is selected.
A "High" mode designation signal is output from one terminal. Here, when in T priority mode, the terminal peak is “High”
In the A priority mode, the terminal (5) is set to "High", and in the P mode, the terminal (P) is set to "IIIgh",
In the M mode, the terminal M becomes "IIigh".

In the exposure calculation circuit (25), the terminal (1) is “High
”, the calculation is performed, and when the terminal hole is “High”, the calculation is performed, and when the terminal (8) is “High”, the calculation is performed, and the terminal (M ) or “High”, Avs −Avo −(
10) is performed. In addition, the exposure calculation circuit (25
), the set or calculated exposure time data Tv is sent to the latch circuit (26), and the calculated aperture step number data Av-Avo is sent to the latch circuit (27), and the set or calculated aperture value data Av is latched. It is sent to the circuit (28).

The frequency divider (DI 5 ) is a power-on reset signal (1
)OR) and input the clock pulse (cp) from the oscillator (PG) in Figure 1 (7) to generate a pulse with a constant period (for example, 16 Hz).The one-shot circuit (O8u) is a frequency divider. A pulse of "Hj g h" is output at each rise of a pulse of a constant period from (DIs).

The D flip-flop (DFxa) is reset by the power-on reset signal (PAR), and if the photometry switch (Sl) in Figure 1 remains closed, the output of the inverter (INt) will become “High”. Therefore, the Q output becomes 'High' at the rise of the first pulse from the one-shot circuit (0811).The gate of the AND circuit (AN46) is opened by this "High" output, and the one-shot circuit A constant period pulse from (O81t) is given to the input terminal (CL) of the I) flip 70 tube (DF 16) and the AND circuit (A N 47) via the AND circuit (AN46).Here, D In the flip-flop 7' (DFta), the release switch (S3) that turns on the power and the back lock switch (S4) that closes in response to the back lock operation remain open (i.e., the shutter release switch and the back lock switch remain open). When the operation is not performed), the output of the AND circuit (A N 46) is “Low”, so the Q output is “High”.
It becomes. This "High" output opens the gate of the AND circuit (AN47), and the above-mentioned constant period pulses are sent to the latch circuits (26), (27'), (2
8) (This is given. Latch circuits (26), (27),
(28) uses this pulse to latch data on the exposure time, number of stops, and aperture value from the exposure calculation circuit (25). Therefore, the photometry switch (Sl) is closed, the lock switch (S4) and the release switch (S3) are closed.
) remains open, that is, when only photometry operation is being performed, the latch circuits (26), (27), and (28) are exposed according to the cycle of the pulse from the one-shot circuit (0811) (for example, 16 Hz). Data from the arithmetic circuit (25) is sequentially latched.

When the photometry switch (Sl) is opened, the inverter (IN
The output of I) becomes "Low" and the Q output of the D flip-flop (1) F15) becomes "Low", the gate of the AND circuit (A N 46) is closed and the output from the one-shot/so-to circuit (0811) is The latch signal is no longer output.

When the light metering switch (Sl) is closed and the lock switch (S4) is closed, the light metering switch (INI1) is closed.
), the output of the OR circuit (O)L15) becomes “Hi”
So, 11. Reading of data from one accessory has been completed (i.e. (3t3rt). The terminal is “bow”.
”), the output of the AND circuit (AN48) becomes “High”.
The Q output of the 70-tube (,1) F le) is used as a latch signal, which becomes "Low" at the falling edge of the pulse from the AND circuit (AN46), and the gate of the AND circuit (AN47) is closed. The latch signal will no longer be output.

Therefore, latch circuits (26), (27), (2
In step 8), the exposure control factor is cleared by the last false signal when the armature switch (S4) is closed, and no data is updated thereafter.

When the release switch (S3) is closed next with the AE locked state (at this time, the Q output of the D flip-flop (DF16) remains "High"), the inverter (
INIO) output becomes “High” and data reading from the accessory is completed (2
When the ar terminal is “Low”, the output of the AND circuit (AN aa) becomes “High” and the free
The knob 70 knob (FF45) is set at this rising edge, and the terminal (tL) becomes "High". This terminal (1-
At the rising edge of LL), the latch decoder (35) receives the first signal.
The data of the aperture error amount at the time of opening of the release switch (S3) given from the register (LEG 12) in the figure is latched and decoded into data ΔAV2 for calculation.

Then, in the subtraction circuit (36), Ay-ΔAV2-Avo-(1
The calculation 1) is performed. Also, the “Hi” of the terminal (RL)
gh” sets the flip-flop 70 (FFI switch) shown in FIG. 1 and closes the gate of the AND circuit (A ) is “High”
After a certain period of time has passed, the output of the delay circuit (30) becomes "High", the release circuit (31) operates, and the exposure control operation is started.

Note that during this certain period of time, it is determined whether the power supply voltage of the camera is appropriate, whether there is camera shake, etc.

The aperture subsidiary (37) outputs a quantity corresponding to the data from the subtraction circuit (36), ie Av-ΔAV2-Av.

Stop down from the maximum aperture. Therefore, the diameter of the aperture [ ] that has been narrowed down has a value corresponding to Av - ΔAV2,
Since the aperture error amount at this time is generalized to 2, the actual effective aperture is (Av - ΔAV2) + ΔAV2 = Av
-(12), and the aperture error amount ΔAv+ at the time of locking
The aperture value is controlled to match the appropriate aperture value output from the exposure calculation circuit (25).

The shutter control device (32) also includes an exposure calculation circuit (25).
) for a period of time based on data from
”, the electromagnet (Mg) is made conductive to prevent the shutter opening operation and control the exposure time. In this way (7), when the exposure is controlled based on the eaves lock, the number of aperture stages is set to p IJ-Z. Since the aperture control is performed by correcting the aperture error to a value that takes into account the amount of aperture error at the time, the effective aperture is accurately controlled to the calculated or set value.

When the output of the shutter control circuit (32) becomes 'High' (this is reversed and the electromagnet < Mg) becomes non-conductive and the shutter opening operation starts, the output of the delay circuit (33) after a certain period of time determined by the delay circuit (33). The terminal (CM) is “High”
”. This signal is output from the OR circuit (01-LIO
), the flip-flop (FF1o) is reset, the gate of the AND circuit (AN40) is opened, and the read operation from the accessory becomes possible again. Further, the exposure time display device (34) displays the exposure time based on the exposure time data Tv from the latch circuit (26), and the aperture display device (38) displays the exposure time based on the aperture data Av from the latch circuit (28). Displays the controlled effective aperture value.

Next, a case of normal photographing without performing a locking operation will be described. When the release switch (S3) is closed while the photometry switch (Sl) is closed, the inverter (I
When the output of N+o) becomes "High" and the reading of data from the accessory is completed and the start signal (star) becomes "LIOW", the output of the AND circuit (AN4g) becomes "High". This causes D to go high at the falling edge of the pulse from the AND circuit (AN46).
Q output of flip-flop (DPI6) is “Low”
Then, the gate 4 of the AND circuit (AN4) is closed and no further latch pulses are output.On the other hand, the Q output of the D flip-flop (DF16) becomes "High", so the AND circuit (AN45) The output of the flip-flop (FF4s) is set to "High" and the terminal (RL) becomes "High".Then, the delay circuit (
30) After a certain period of time, the release circuit (31) operates to start the exposure control operation. Here, set the metering switch (
SL) and the release switch (S3) are closed almost simultaneously, or even if the release switch (S3) is closed first, the photometry switch (Sl) is closed and the power-on reset signal (1 -'Of(,) resets the divider (DIs) and the first latch pulse is output from the one-shot circuit C08zx), and the Q output of the flip-flop (DF16) is High until the output falls. ”, so the AND circuit (ANA
7), one latch pulse is reliably output.

Therefore, the exposure control factors are the latch circuits (26) and (2
7).

The exposure control operation will not start until the time (28) is latched. This is also the case with the baroque switch (S4), and the A
Even if the E lock switch (S switch) is closed, latching is not performed, and the photometry switch (81) is closed while the M lock switch (S4) remains closed, and the first latching pulse is sent to the AND circuit. Since the gate of the AND circuit (AN47) is closed after being output through (AN47),
The exposure control factor at the time the photometry switch (Sl) is closed will be latched.

When the terminal (RL) becomes "High''', the latch decoder (35) latches the aperture error amount data from the register (REGlg) in FIG. 1 and outputs the calculation data ΔAv.
changed to. At this time, latch circuits (26), (27)
.

(28) latches the dropout control factor based on the exposure value Ev from which the term of the aperture error amount ΔAv included in the photometric output is removed as described above. and subtraction circuit (36)
Then AV-ΔAv-Avo-(11
) is performed, and the aperture control device (37) narrows down the aperture from the open aperture: LJ) by an amount corresponding to this data. Therefore, the narrowed aperture corresponds to Av - blood v (
7, but since the aperture error amount is ΔAv fl, the effective aperture is (Av - ΔAv) ten ΔAv = Av - =
(12), and the aperture value is controlled to be equal to the aperture value from the exposure calculation circuit (25) [7]. In addition, the display device (38
), the effective aperture value to be controlled is displayed, and the exposure time is also calculated to determine whether it is an exposure time that is not affected by the aperture error amount ΔAv, and the display is performed based on this, and the aperture error amount ΔAv is being outputted in photometry as before. Since calculations are performed with the image still included in the image, there is no problem that camera shake is likely to occur.

, - In the embodiments shown in FIGS. 1 and 3, data regarding the amount of aperture error corresponding to the set focal length of the zoom lens is transmitted from the zoom lens to the camera body, but other information of the zoom lens is Based on G), it can be modified so that the data of the aperture error amount can be automatically detected on the camera body side. In other words, if the shortest focal length and longest focal length of the zoom lens are known, the ROM in the circuit section of the camera body allows the camera body to know which zoom lens is being used.
Based on these two focal length data, specify the upper bit of the address in the ROM in the camera body, and specify the lower bit with the set focal length data to specify the address and calculate the aperture error amount. All you have to do is get the data. With this configuration, data on the shortest focal length, longest focal length, and set focal length can be sent from the lens. Furthermore, data indicating the type of lens may be sent instead of the shortest and longest focal lengths.

In addition, in Figure 4, when the data from the subtraction circuit (36) is Av - ΔAv - Avo < Q, the exposure will be underexposed even if the lens aperture is set to the maximum aperture of I7. In case, Av
The mode may be switched to the A-priority mode using o+ΔAv as the set aperture value, the A-priority mode calculations may be performed, the exposure time is recalculated, and the exposure time is controlled based on this.

Also, the aperture value you set A, vo+ΔAv>Avs≧Av.

Even if
It is necessary to perform calculations and control using Avs, and it is also desirable to issue a warning that control using Avs is impossible.

Also, as mentioned above, the amount of aperture error does not change depending only on the focal length, but the amount of aperture error changes depending on both the focal length and the aperture value. For example, when the aperture value is wide open, There is a zoom lens in which the aperture error amount changes accordingly, and the aperture error amount is O on the small aperture side regardless of the focal length. For such a lens, it would be better to specify the ROM address using data corresponding to the focal length and aperture value and output the error amount data. Although we have only mentioned G1 regarding the correction of the aperture error amount, there are also lenses whose effective aperture changes according to the rotation of the distance adjustment member of the lens and the distance ring I7.Especially macro lenses, etc. In the case of a lens with a large extension amount, the effective aperture changes greatly.

Therefore, as in the present invention, correction can be made by reading the aperture error amount corresponding to the distance R&adjustment from the lens into the camera body.

In the above description, a case has been described in which lenses such as a zoom lens or a macro lens are interchangeably attached to the camera body, but the present invention is an interchangeable lens in which these lenses are interchangeably attached to the camera body. However, the present invention is not limited to this, and can also be applied to a case where a camera body lens, such as a zoom lens, is integrated in a non-replaceable manner.

Next, when taking flash photography using an electronic flash device, the photometric integral value of the photometric circuit built into the electronic flash device is set to a predetermined value corresponding to the camera's predetermined aperture value (at which point the flash stops flashing). How to control the light emission with the configured electronic flash device, and use the fact that the product of the distance to the subject and the camera aperture value corresponds to the amount of light emitted by the electronic flash device (equivalent to the so-called guide number ON). When using a zoom lens as a photographic lens, it is necessary to set the aperture value of the camera's photographing lens to a predetermined setting value or calculated value. Although it is applied to such cases, as an example, the case of flash photography in which the aperture value of the camera is determined based on the amount of light emitted from the electronic flash device Iv and the distance Dv to the subject is shown in Fig. 5. The following is an explanation based on this.

FIG. 5 is a block -□ showing the circuit configuration of an embodiment of the present invention in the case of flash photography. In the figure, the data output device (61) is the register (R1-Xj2) to
(H, 14G13), distance data from the device to the subject (Dv) and open aperture value data (Avo)
and aperture error amount data (ΔAv) are output.

The aperture value calculation circuit (63) for flash photography is an electronic flash unit (63).
2), the distance data (Dv) provided from the data output device (61), and the film sensitivity data (Sv) provided from the film sensitivity data output circuit (21), Sv +Iv − 'D
Calculate v = Av and obtain aperture value data (
Av) is output. This aperture value data (Av) is displayed by an aperture display circuit (66) and is also provided to an aperture stage number calculation circuit (64). This aperture stage number calculation circuit (64
) is also given the open aperture value data (Avo), and the number of aperture stages for controlling the aperture to the appropriate aperture value (Av) is calculated based on the difference between the two. Note that the open aperture value data (A v o, ) is usually the wide open F value. The correction circuit (65) uses the aperture stage number data (Av-) obtained by the aperture stage number calculation circuit (64).
Effective aperture stage number data (Av - Av) based on Avo ) and aperture error amount data (ΔAv) given from the data output device □ (61).

-, Mv). Based on this data, the diaphragm is controlled by the diaphragm control circuit (67), and the diaphragm error amount data (ΔAv) is canceled out by the diaphragm, so that the aperture diameter corresponds to the aperture value Av to be controlled.

In the above explanation, for convenience of explanation, the circuit configuration of the embodiment is configured with a logic circuit, but instead, the operation is programmed and stored in a microprocessor (CPU), and the CPU
It goes without saying that the operation may be controlled sequentially via the .

Effects The present invention provides an aperture value output device that outputs aperture value data to be controlled and an aperture diaphragm that outputs the aperture error amount data of the zoom lens in a camera with a zoom lens in which the amount of aperture error changes depending on the focal length. It comprises an error amount data output device and a correction device that corrects the aperture value data based on the aperture error amount data, and the aperture value when the aperture value is actually stopped down by the correction device is the aperture value to be controlled. As a result, the aperture value that is calculated or set to be controlled always matches the aperture value at the time of shooting, which eliminates the drawback of the conventional method that the exposure is performed based on a control date that is different from the desired exposure factor. It can be resolved.

In addition, according to the embodiment of the present invention, the aperture value is displayed based on aperture value data that does not include the aperture error quantity S, so that the aperture value displayed is more open than the actual one, as in T mode and P mode. This also eliminates the inconvenience of displaying the side.

[Brief explanation of the drawing]

FIG. 1 is a circuit diagram showing a circuit configuration of a data reading section on the camera body side that includes an aperture error amount data output device in one embodiment of an exposure control device of the present invention, a circuit diagram showing a circuit configuration of a lens, and a circuit diagram showing a circuit configuration of a lens circuit. FIG. 4C is a block diagram showing the circuit structure of one embodiment of the present invention, and FIG. 5 is a block diagram showing the circuit structure of another embodiment. 25, 63... Aperture value output device, 19.35...
Aperture error amount data output device, 36, 65...correction device, 37.67...aperture control device. Applicant: Minolta Camera Co., Ltd. Procedural Amendment Written by Kazuo Wakasugi, Commissioner of the Japan Patent Office1, Indication of the case, Patent Application No. 55187 of 1982, Name of the invention, Development of a camera with a zoom lens 1rll Gosou f13 Person making the correction Relationship to the incident Applicant address 2-30 Azuchi-cho, Higashi-ku, Osaka Osaka Kokusai Building name (607) Minolta Camera Co., Ltd. Jihatsu i+
1゛I correct 5 Target of correction

Claims (1)

[Claims] 1. A zoom lens in which an aperture error amount corresponding to the difference between a calculated or set aperture value and an aperture value when the aperture is actually stopped down based on the aperture value changes depending on the focal length. An aperture value output device that outputs data related to a calculated or set controlled aperture value in a camera that is fixedly installed or can be attached, and an aperture value output device that outputs data related to the aperture value that is calculated or set, and an aperture error amount that is related to the focal length of the zoom lens. an aperture error amount data output device that outputs data; and the aperture error amount data is added to the aperture value data of the aperture value output device, and the aperture value when the aperture is actually narrowed down becomes the aperture value to be controlled. Exposure of a camera with a zoom lens, characterized in that it is equipped with a correction device that calculates aperture value data, and an aperture control device that controls the diameter of the aperture based on the aperture value data corrected by the correction device. The control unit ``P, 2. The aperture value output device 嵯 includes a photometry circuit that measures the intensity of the object light that has passed through the zoom lens and outputs a photometry value that includes data regarding the aperture error amount of the zoom lens, and the photometry circuit. and an arithmetic circuit that calculates data regarding an aperture value that does not include the aperture error amount data according to the photometric output of the aperture error amount data and the aperture error amount data of the aperture error amount data output device. Exposure control device for a camera with a zoom lens according to A. The camera includes an aperture display device that displays an aperture value to be controlled, and data output from the aperture value output device is input to an input end of the aperture display device. An exposure control device for a camera with a zoom lens according to claim 1 or 2 of the appended claims.