JPH07333675A - Film information reader - Google Patents

Abstract

PURPOSE:To provide a film information reader capable of accurately reading information about a film on a film cartridge. CONSTITUTION:This camera in which the film cartridge having an information recording disk 3 integrally rotating with a spool 2 inside a film case 1 and symbolizing and recording the information about the film 6 is used is provided with a photoreflector 21 reading out the information about the film 6 recorded on the recording disk as the disk 3 rotates, a film feeding motor 23 making the spool 2 rotate in a direction opposite to the film feeding direction, and a controlling means for reading information which detects that the film cartridge is loaded on the camera and controls to read out the information about the film by the photoreflector 21 while making the spool 2 rotate in the direction opposite to the film feeding direction by the motor 23.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a film information reading apparatus, and more particularly to a film information reading apparatus for a camera using a film cartridge having a recording disk on which information related to the film is encoded and recorded.

[0002]

2. Description of the Related Art Conventionally, in a camera using a film cartridge having a disk that rotates integrally with a spool in a film cartridge and information about the film is recorded as bar code information, the bar code is fed while the film is being fed. A technical means for reading information with an optical detecting means or the like is disclosed in US Pat. No. 5,032,854.

In the above technical means, the bar code is read while the film is fed by using the motor. However, at the start of feeding the film, the speed fluctuation is so great that a read error occurs due to the speed fluctuation. was there. Considering this problem, the above-mentioned US Pat. No. 5,032,854 also proposes a technical means for starting the reading of the bar code after a predetermined time has elapsed after the film feeding is started and the film feeding speed is stabilized. There is.

In the camera, the film feeding speed, that is, the rotation speed of the disk on which the bar code is recorded, fluctuates greatly in the following cases.

1) Time required for the motor to reach a stable rotation speed at the start of driving the motor.

2) A time zone in which the leading edge of the film passes the front surface of the exposure opening. On the front surface of the exposed opening, there is a narrowed area sandwiched between the film rail surface and the pressure plate that presses the film from the rear, and the load on the motor becomes heavy during the time when the leading edge of the film passes through this narrowed area. Because of this, the speed fluctuates significantly.

3) A time period from when the leading end of the film starts to be wound around the film take-up spool of the camera until when the film is completely wound.

Therefore, from the time when the film is fed to the time when the leading end of the film is completely wound around the film take-up spool of the camera, there are some fluctuations in the feeding speed. It is desirable to start reading the bar code after the period.

[0009]

However, when the bar code reading is started after waiting until the leading end of the film is wound around the film take-up spool of the camera in this way, the following problems occur. Must be considered.

A) The length of the leader portion of the film (the portion from the leading end of the film to the leading frame of the film) is not infinitely long, but is a finite length due to the manufacturing cost of the film.

B) To read the bar code, the film must be fed to some extent.

C) The feeding speed of the film varies depending on various conditions. For example, the hardness of the film changes due to changes in temperature and humidity. Therefore, the load of the drive motor varies depending on the conditions. It also varies depending on the degree of battery consumption. Therefore, even under bad conditions (when the film feeding speed is slow), it is necessary to set the time until the leading edge of the film is sufficiently wound around the film take-up spool of the camera.

For the reasons given in the above a) to c), if the bar code is read after a sufficient time has passed, the bar code may be read over the leading frame of the film. .

The present invention has been made in view of the above problems, and it is an object of the present invention to provide a film information reading device for accurately reading information about a film in a film cartridge.

[0015]

In order to achieve the above object, the first film information reading device according to the present invention rotates integrally with the spool in the film cartridge, and the information on the film is coded and recorded. In a camera using a film cartridge having a recording disk, the information reading means for reading information about the film recorded on the recording disk with the rotation of the recording disk, and the spool in the film cartridge, A motor driving unit for rotating the film in the direction opposite to the film feeding direction, and detecting that the film cartridge is loaded in the camera, rotating the film cartridge in the direction opposite to the film feeding direction by the motor driving unit, The information reading means controls the reading of information about the film. It includes an information reading control means.

To achieve the above object, a second film information reading device according to the present invention is the first film information reading device, wherein the information reading control means performs reading of information by the information reading means. The driving voltage of the motor driving means is kept constant during the operation.

In order to achieve the above object, the third film information reading apparatus according to the present invention is the first film information reading apparatus, wherein the information reading control means has a start bit pulse when reading the start bit. It further has an information reading standard setting means for measuring the width and setting the time judgment standard of the information following the start bit based on the pulse width.

[0018]

The first film information reader according to the present invention comprises:
The information reading means reads the information about the film recorded on the recording disk as the recording disk rotates. Further, the spool in the film cartridge is rotated by a motor driving means in a direction opposite to the film feeding direction. Further, the information reading control means detects that the film cartridge is loaded in the camera, and while the motor driving means rotates the film cartridge in a direction opposite to the film feeding direction, the information reading means displays information about the film. Read control is performed.

According to a second film information reading apparatus of the present invention, in the first film information reading apparatus, the motor is provided while the information reading control unit is reading information by the information reading unit. The drive voltage of the drive means is constant.

A third film information reading apparatus according to the present invention is the same as the first film information reading apparatus, wherein the information reading control means measures the pulse width of the start bit at the time of reading the start bit. From the pulse width, the information reading standard setting means sets the time judgment standard of the information following the start bit.

[0021]

Embodiments of the present invention will be described below with reference to the drawings.

First, prior to the description of the embodiments of the present invention,
A film cartridge used in a camera to which the film information reading device of the present invention is applied will be described.

FIG. 3 is an external perspective view showing the film cartridge, and FIG. 4 is a sectional view of the essential parts of the film cartridge. Further, FIG. 5 is a front view showing a state in which the film is pulled out from the film cartridge.

This film cartridge has a recording disk that rotates integrally with a spool arranged in the center of the inside thereof and symbolically records information about the stored film. The film cartridge accommodates a film 6 (see FIG. 4) wound around a spool 2 inside a film case 1. This spool 2 is
The upper end of the film cartridge is projected above the case 1, and when the film cartridge is loaded in the camera body, it engages with a fork provided on the camera side.

On the upper part of the case 1, there is arranged an information recording disk 3 in which information on the stored film is recorded as bar code information. The information recording disk 3 is integrally formed like a flange on the spool 2 in the film cartridge. Further, a start bit 4 is provided in the bar code provided on the upper surface of the information recording disk 3 as shown in the figure, and is wider than other bar code patterns. Further, a delivery port 5 for delivering the film 6 is formed at one end of the case 1.

FIG. 4 shows a cross section of the film cartridge, in which the film 6 wound around the spool 2 is housed.

FIG. 5 is a front view showing a state in which the leading end portion of the film is pulled out from the inside of the film cartridge.

In this figure, reference numerals 13, 14, 15
Are the first frame and the second frame on the film 6, respectively.
The exposure unit corresponds to the frame and the third frame. Also, the film 6
Square holes 10, 11 and 12 provided on the film are formed at the upper end of the film for positioning the exposure part corresponding to each frame at a predetermined position on the camera side. Further, in the drawing, reference numeral 16 is a film front end portion, and further reference numeral 17
Is the leading edge of the leading piece. The film tip 1
A predetermined distance L is defined between 6 and the leading edge 17 of the leading frame.

FIG. 1 is a diagram of the main part of the film information reading apparatus according to the first embodiment of the present invention, as viewed from the rear surface of the camera body. Further, FIG. 2 is a view of the main part of the film information reading apparatus as seen from above.

A fork 20 that engages with the upper end of the spool 2 of the film cartridge is provided in the storage chamber in the camera body in which the film cartridge is loaded. A photo-reflector 21 for reading a bar code recorded on the information recording disk 3 is arranged near the upper side of the information recording disk 3.

On the other hand, an aperture is formed at the rear of the photographing optical axis of the camera body, and a spool 22 for winding the photographed film is arranged on the opposite side of the storage chamber across the aperture. Has been done. A film feeding motor 23, which serves as a power source for feeding the film 6, is arranged above the aperture. The transmission force of the driving force from the film feeding motor 23 is switched by the switching mechanism 24 according to the rotation direction of the film feeding motor 23.

The driving force switched by the switching mechanism 24 is transmitted to the fork 20 and the spool 22 via transmission mechanisms 25 and 26, respectively. The film feeding operation will be briefly described below.

When the film feeding motor 23 rotates in the first direction, the switching mechanism 24 and the transmission mechanism 25,
By the action of 26, the fork 20 and the spool 22 in the camera are rotated in the CW direction (clockwise) when viewed from above. That is, when the film feeding motor 23 is rotated in the first direction with the film cartridge loaded in the storage chamber, first, the film 6 is sent out from the film cartridge by the rotation of the fork 20 in the CW direction. . When the tip of the film 6 is wound around the spool 22 in the camera, the film 6 is further wound around the spool 22 by the rotation of the spool 22 in the CW direction.

The switching mechanism 24 and the transmission mechanisms 25, 26 are set so that the film winding speed by the rotation of the spool 22 is faster than the film feeding speed by the rotating force of the fork 20. Therefore, after the film 6 is wound around the spool 22 in the camera, the film 6 pulls the fork 20 and the transmission mechanism 25, but the transmission mechanism 25 can idle in the CW rotation direction. It is designed to absorb the difference in the film feeding speed.

On the other hand, when the film feeding motor 23 is rotated in the second direction opposite to the first direction, the mechanisms 24 to
The action of 26 causes the fork 20 to rotate in the CCW direction (counterclockwise). The spool 22 is set in a freely idling state, and the film 6 wound on the spool 22 can be rewound into the film cartridge.

In the figure, reference numeral 27 is the film 6 described above.
It is a portion corresponding to the above aperture. Reference numeral 13 is a portion corresponding to the exposed portion of the leading frame on the film.

The square hole 10 on the surface of the film 6
At the position opposite to the feeding path of the film 6 in order to feed the film 6 by one frame at the time of feeding the film 6.
A photo interrupter 30 for detecting the feeding amount of is provided. Then, when the film 6 is automatically loaded or after the film is taken up and wound up, the film 6 is fed by a necessary amount, and the edge on the leading side of the square holes 10 to 12 comes to the front of the photo interrupter 30. The drive of the film feeding motor 23 is stopped. As shown in FIG. 2, the photo interrupter 30 is arranged so that the light emitting portion 30a and the light receiving portion 30b sandwich the film 6.

FIG. 6 is an electric circuit diagram showing the control circuit in the above embodiment. The control circuit will be described below along the flow of signals.

The power supply voltage of the power supply battery 50 is equal to that of the booster circuit 52.
Is boosted to a predetermined constant voltage by a microcomputer (CPU) 51 which controls the entire film information reading device.
And so on. The CPU 51 has a plurality of input / output terminals C
1 to C12 are provided. The input terminal C1 has a rear cover detection switch 5 for detecting opening / closing of a rear cover (not shown).
8 is connected. Although not shown, the rear lid is a lid for loading and unloading the film cartridge in the camera body to which the film information reading apparatus of this embodiment is applied. The rear cover detection switch 58 is turned on when the rear cover is open and is turned off when the rear cover is closed. In the figure, reference numeral 53 is a pull-up resistor,
The input terminal C1 is pulled up via the resistor 53.

The photo-reflector 21 for reading the bar code provided on the information recording disk 3 of the film cartridge is connected to the output terminal C2 and the input terminal C3 of the CPU 51. The anode side of the light emitting diode 59 in the photo reflector 21 is connected to the output terminal C2 via the current limiting resistor 54.
And the collector of the phototransistor 60 is connected to the input terminal C3. In the figure,
Reference numeral 55 is a pull-up resistor.

The photo interrupter 30 for detecting the film feeding amount is connected to the output terminal C4 and the input terminal C5 of the CPU 51. The light emitting diode 61 in the photo interrupter 30 has its anode side connected to the output terminal C4 via the current limiting resistor 56, and the photo transistor 62 has its collector connected to the input terminal C5. In the figure, reference numeral 57 is a pull-up resistor.

The film feeding motor 23 is driven by a driver circuit composed of a bridge transistor composed of transistors 70-73. In the figure, reference numerals 66 to 69 denote the base resistances of the transistors 70 to 73, respectively.
One end of each of 6 to 69 has an output terminal C of the CPU 51.
It is connected to the 8, C7, C9, and C6 output terminals.

When the film feeding motor 23 is rotated in the first direction, the signal from the output terminal C8 of the CPU 51 is set to "L" level, the signal from the output terminal C6 is set to "H" level, and the transistor 70 is turned on. , 73 is turned on. At this time, the output terminal C9 is set to "H" level,
The output terminal C7 is set to "L" level and the transistor 7
1, 72 are turned off.

Further, the film feeding motor 23 is connected to the second
Output terminal C of the CPU 51 when rotating in the direction of
9 is set to "L" level and the output terminal C7 is set to "H" level to turn on the transistors 72 and 71. At this time, the output terminal C8 is set to the "H" level, the output terminal C6 is set to the "L" level, and the transistors 70 and 73 are turned off.

Further, when the film feeding motor 23 is stopped, the output terminals C6 and C7 are set to the "H" level, the transistors 71 and 73 are turned on, and the film feeding motor 23 is short-circuited. At this time, the output terminals C8 and C9 are set to "H" level to turn off the transistors 70 and 72.

A constant voltage output circuit 63 for generating a constant voltage for driving the film feeding motor 23 with a constant voltage is connected to the terminals C10 to C12 of the CPU 51. The output terminal of the constant voltage output circuit 63 is an operational amplifier 64.
Of the operational amplifier 64, and the output terminal of the operational amplifier 64 is connected to the base of the PNP transistor 65. The collector of the transistor 65 is input to the non-inverting input terminal of the operational amplifier 64 and is connected to the emitters of the transistors 70 and 72.

The constant voltage output circuit 63 includes the CPU 5
A constant voltage is generated according to the control signal from the first output terminal C10 to C12. As a result, the operation of the operational amplifier 64 and the transistor 65 fixes the upper end of the bridge transistor for driving the film feeding motor 23 to a predetermined constant voltage.

Next, the operation of the film information reading apparatus of this embodiment will be described with reference to the flowchart shown in FIG. In the flow chart shown in FIG. 7, the photographer opens the rear lid of the camera to load the film cartridge, then closes the rear lid, and then the camera reads the bar code on the film cartridge to end the autoloading. The operation up to is shown.

In step S1, the CPU 51 monitors the input signal of the input terminal C1. When the level is changed from "L" level to "H" level, the CPU 51 determines that the rear lid is closed and proceeds to step S2. From "L" level to "H"
If the level is not switched, the determination in step S1 is repeated. In step S2, the CPU 51 sends a control signal to the constant voltage circuit 63 to set a predetermined constant voltage.

Next, in step S3, the CPU 51 sets the signal at the output terminal C9 to "L" level and sets the output terminal C7 to "H".
The level is set to start driving the film feeding motor 23 in the second direction. Next, in step S4, the signal at the output terminal C2 is set to the "H" level to activate the light emitting diode 59, and the barcode can be read.

Next, in step S5, a 100 msec timer is operated. This timer is a waiting time until the rotation speed of the film feeding motor 23 rises to a constant rotation speed. This is because if the bar code reading is started before the rotation speed of the film feeding motor 23 rises to a constant value, the bar code may be erroneously read. Next, in step S6, the start bit is read.
As shown in FIG. 3, the bar code has a start bit 4, and the pattern of this bit is wider than the patterns of other bits and is blackened. This step S6 is a step of reading the start bit 4 separately from other bits.

Details of the start bit detection in step S6 will be described with reference to the flow chart shown in FIG.

In step S100, the timer TM
Reset 1 and start. Next, in step S101, the input terminal C3 is monitored and the "L" level →
If the "H" level is selected, the process proceeds to step S102. In step S102, the timer TM2 is reset and started. Next, in step S103, the input terminal C3 is monitored again, and if the "H" level is changed to the "L" level, the process proceeds to step S104.

In step S104, the timer TM2 is stopped, and then in step S105,
The magnitude relationship between the count value of the timer TM2 and the predetermined value TST is compared. When TM2 ≧ TST, it is determined to be the start bit, and then in step S106,
Stop the timer TM1 and return. Also TM
When 2 <TST, it is determined that the information bit is not the start bit but the normal information bit, and the process returns to step S101.

On the other hand, if the input terminal C3 is not switched from the "L" level to the "H" level in step S101, the process proceeds to step S107 to compare the count value of the timer TM1 with a predetermined value TMAX, TM1 <
If it is TMAX, the process returns to step S101. Also TM1
If ≧ TMAX, then in step S108 the timer T
M1 is stopped, the motor drive is turned off in step S109, the output terminal C2 is set to "L" level in step S110, the light emitting diode 59 is turned off, and step S11 is performed.
In No. 1, a warning display indicating that there is no film is displayed on the display element outside the camera. Then, the process returns to step S1 in FIG. If the photographer does not load the film cartridge and closes the rear lid, the barcode cannot be read, and this process is performed.

Returning to FIG. 7, after step S6, the process of step S7 is performed. In step S6, the pulse width of the start bit 4 is measured when reading the start bit and stored in the timer TM2.
At 7, the time judgment standard of other bits following the start bit is set based on the count value of TM2.

The bar code pattern provided in the film cartridge used in the present embodiment is a start bit followed by 12 patterns of alternating white / black / white.
There are two types of these patterns, a white pattern and a black pattern, a wide pattern and a narrow pattern. This pattern is read in step S8 to determine the length of the pulse width, but if the threshold for determining the pulse width is set to a fixed value, the following problems will occur.

The number of rotations of the motor fluctuates depending on the degree of consumption of the battery of the power source of the camera, the ambient temperature and humidity, variations in mechanical parts, and the like. Therefore, there is a risk of making a mistake in the determination with a fixed threshold value due to these fluctuation factors.

Details of step S7 will be described below with reference to the flow chart shown in FIG.

In step S201, if the count value of TM2 is larger than the predetermined value TM2A, step S2
In step 04, the predetermined value TTHA is stored in TTH and the process returns. Next, at step S202, when the count value of TM2 is equal to or more than TM2B and is less than TM2A, the routine proceeds to step S205, where a predetermined value TTHB is set to TTH.
Store and return. When the count value of TM2 is less than TM2B, a predetermined value TTHC is stored in TTH in step S203 and the process returns. Here, the constants are determined so that TTHC <TTHB <TTHA. That is, in the flowchart shown in FIG. 9, the rotational speed of the film feeding motor 23 is divided into three stages according to the count value of TM2, and the value of TTH is set according to those rotational speeds.

Returning to FIG. 7, after step S7, the process proceeds to step S8. Here, details of the step S8 are shown in FIG.
This will be described with reference to the flowchart shown in FIG.

First, in step S300, the loop counter I is set to 0. Next, in step S301, the timer TM3 is reset and started. Next, in step S302, the state of the input terminal C3 is monitored, and if the state changes, then in step S303, the count of the timer TM3 is stopped.

Next, in step S304, the count value of TM3 is compared with TMH, and if TM3 ≧ TTH, it is determined to be a long pulse, and 1 is stored in the Y (I) flag. If TM3 <TTH, it is determined that the pulse is short and the Y (I) flag is set to 0 in step S306.
Memorize Then, in step S307,
If I = 11, the process returns, and if I = 11, then I is incremented by 1 in step S308 and then step S3.
Return to 01. By passing through the barcode reading flow shown in the flowchart of FIG. 9, 12 pieces of pattern information following the start bit are read, and Y (0) to Y (0) to
(11) Store in flag.

Returning to FIG. 7, in step S9 following step S8, the output terminal C2 is set to L to turn off the light emitting diode 59, and in step S10, the motor drive of the film feeding motor 23 is turned off. In step S11, motor shot braking is performed.
Here, the CPU 51 sets the output terminals C6 and C7 to the "H" level, and then sets the output terminals C6 and C7 to the "L" level after 50 msec has elapsed.

This completes the barcode reading sequence.

Next, in step S12, the film is sent out, that is, the film is loaded.
First, in step S12, the constant voltage of the motor is set. Here, the motor constant voltage to be set is VM2, which is set higher than the constant voltage VM1 set in step S2. When reading the bar code, it is convenient that the drive voltage of the film feeding motor 23 is low. The reason is that if the driving voltage is too high, the number of rotations of the motor becomes high and the barcode information may be missed.

For the convenience of the circuit, the output voltage of the motor constant voltage circuit cannot be set higher than the output voltage of the power supply battery 50. The output voltage of the power supply battery may be considerably lowered due to the degree of battery consumption and the influence of temperature and humidity. In addition, the power supply battery 50 is changed by the fluctuation of the driving load of the film feeding motor.
Output voltage fluctuates, but VM1 is set to a low value so that the drive voltage of the film feeding motor does not fluctuate even if these fluctuations occur. On the other hand, when the film is fed out, there is no problem even if the rotation speed of the film feeding motor 23 fluctuates to some extent, so VM2 is set higher than VM1.

Next, in step S13, the film feeding motor 23 is started to be driven in the first direction. Here, the CPU 51 sets the output terminal C8 to L and the output terminal C6 to "H" level. In the next step S14, the output terminal C4 is set to the "H" level to put the light emitting diode 61 into the operating state. Next, in step S15, the input terminal C5 is monitored, and when the state of the input terminal C5 is switched from the "H" level to the "L" level, the process proceeds to step S16 to set the output terminal C4 to the "L" level,
The light emitting diode 61 is turned off, the drive of the film feeding motor is turned off in step S17, and then the short brake is applied to the film feeding motor in step S18 to end the sequence.

Here, step S18 is the above step S1.
Same as 1. The sequence of steps S12 to S18 is a sequence for sending the film to the position where the leading edge 17 of the square hole 10 corresponding to the leading frame 13 is in front of the photo interrupter 30. Here, while the space between the light emitting portion 30a and the light receiving portion 30b of the photo interrupter 30 is blocked by the film, the transmitted light amount of light is small, but when the square hole 10 is in front, the transmitted light amount becomes large. Therefore, the state of the input terminal C5 is switched from the "H" level to the "L" level.

FIG. 11 shows the driving state of the motor and the input terminal C3 in the sequence for reading the bar code.
7 is a timing chart showing a temporal change of the state of FIG.

In FIG. 11, the upper part shows the driving timing of the film feeding motor in the second direction, the middle part shows the timing of the short brake of the film feeding motor, and the lower part shows the potential of the input terminal C3. First, at time t3, the driving of the film feeding motor 23 is started. And t-3 ~
t-2 is 100 ms in step S5 (see FIG. 7).
It is a period corresponding to the ec timer.

This period is a period in which the rotation speed of the film feeding motor rises. Then, at time t-2, the start bit detection subroutine (step S6) is started,
The start bit detection ends at time t0. Where t-
The period of 1 to t0 corresponds to the count value of the timer TM2. In step S7, TTH is determined according to the count value TM2, and then, in step S8, bar code information (pulse width) that appears one after another during t0 to t12 is read, and Y ( 0) ~
The bar code information is stored in the Y (11) flag. Then, at time t12, the drive of the film feeding motor 23 is turned off, and the short brake of the film feeding motor 23 is started. Then, at time t13, the short brake is turned off.

As described above, according to the above-described embodiment, after the film is loaded, the bar code is read by rotating the film feeding motor in the direction opposite to the film feeding direction. It is possible to prevent a problem that occurs when the barcode is read while driving the film feeding motor, that is, a problem that the position of the leading frame is exceeded after the barcode is read.

Further, compared with the case where the film feeding motor is rotated in the film feeding direction, the load of the film feeding motor is small and the load fluctuation is small, so that the bar code is kept at a stable motor rotation speed. Can be read, and the probability of erroneous reading is reduced.

Next, a second embodiment of the present invention will be described.

The structure of the second embodiment is similar to that of the first embodiment, but part of the operation is different. The operation of the film information reading apparatus of the second embodiment will be described below with reference to the flow chart shown in FIG.

In the second embodiment, after the step of step S7 (see FIG. 7) in the first embodiment,
2 is performed, and then step S in FIG.
It is supposed to return to 9.

First, in step S500, the loop counter H is set to 0. Next, in step S501, the barcode is read. Step S501 is
It is the same as the sequence shown in FIG. Next, in step S502, the information stored in the Y (0) to Y (11) flags is transferred to the YA (0) to YA (11) flags. Then, in step S503, the barcode is read again.

Next, in step S504, Y (0)-
The information stored in the Y (11) flag is changed to YB (0) to YA.
(11) Transfer to the flag. Then, in step S5
In 05, the information stored in the YA (0) to YA (11) flags is compared with the information stored in the YB (0) to YB (11) flags, and if they match, the bar code information is determined to be normal. It is determined that the data has been read, and the process proceeds to step S9 in FIG.

If they do not match in step S505, the flow advances to step S506 to read the barcode again, and then in step S507 YB
(0) -YB (11) Information stored in the flag is changed to YA
(0) to YA (11) flags are transferred, and then step S
At 508, the information stored in the Y (0) to Y (11) flags is transferred to the YB (0) to YB (11) flags.
Next, in step S509, the loop counter H is set to 1
Just add. Next, in step S510, H = 1
If the value is 0, it is determined that the bar code reading device is out of order, and in step S511, a failure display is displayed on the display element outside the camera. Next, in step S512, the motor drive is turned off, then the output terminal C2 is set to "L" level, and the process returns to step S1 in FIG.

In the second embodiment, in addition to the effect of the first embodiment, the barcode information is read twice and if they match, it is determined that the barcode information is normal, and the process proceeds to the next step. Therefore, even if a noise or the like is generated in the control circuit system during the reading of the barcode and the reading is mistaken, the erroneous reading can be eliminated.

Although the information error is detected by reading the information twice in the second embodiment, the information error may be detected by another method.
For example, a method of detecting an error in information by checking a combination of impossible information, or counting the number of switching edges (at the input terminal C3) from the end time point of a start bit to the start time point of the next start bit is determined. If the count value is not within the range, the method may be considered as an error of information, or a method of detecting an abnormally long pulse or an abnormally short pulse and making an error if there is any of these.

[Additional Notes] According to the embodiment of the present invention as described in detail above, the following constitution can be obtained. That is, (1) in a camera using a film cartridge having a recording member that rotates integrally with a spool in the film cartridge and records information about the film,
The information reading means for reading the information on the film recorded on the recording member as the recording member rotates, and the spool in the film cartridge, both in the film feeding direction and in the direction opposite to the film feeding direction. Detecting that the motor drive means that can be rotated and the film cartridge is loaded in the camera,
A film information reading device comprising: an information reading control unit that controls reading of information related to the film by the information reading unit while rotating the motor driving unit in a direction opposite to the film feeding direction.

(2) The information reading control means starts reading information by the information reading means after a lapse of a predetermined time after starting the operation of the motor driving means. The film information reading device described in 1.

(3) The information reading control means further includes an information error detecting means for detecting an error in the information read by the information reading means, wherein the film is described in (1) above. Information reader.

(4) In the above (3), the information reading control means repeatedly reads the information within a predetermined number of times when the information error detecting means detects an error in the information. The described film information reading device.

(5) The information reading control means suspends reading of information when the information cannot be read even after reading the information a predetermined number of times, as described in (4) above. Film information reader.

(6) The film information reading apparatus according to (5), further comprising display means for displaying a warning when the information reading control means stops reading the information.

(7) The information error detecting means repeatedly reads the information, and judges that the read information is erroneous when the information read twice consecutively does not match. The film information reading device described in (4).

(8) In a camera that uses a film cartridge having a recording member that rotates integrally with the spool in the film cartridge and records information about the film, the film in the film cartridge is fed out and rewound in two directions. A film driving means that can be driven by the recording medium, information reading means that reads the information recorded on the recording member, and the information recorded on the recording member when the film is stored in the film cartridge. In response to the read command, the first drive means for causing the film drive means to drive the film in the rewinding direction, and information for the information reading means during the rewinding operation by the first control means. Second control means for performing reading,
An information reading device comprising:

(9) The above (8) is characterized in that the film drive means is provided with a third control means for feeding the film after the information reading operation by the second control means is completed. Information reader.

According to the embodiment described in (1) above, since the film feeding operation is started after the information reading is completed, the information reading is surely performed without being completed halfway, and Since no load is applied other than rotating the recording member, uneven rotation does not occur, and therefore information can be read accurately.

According to the embodiment described in (2) above, since the information is read after the elapse of a predetermined time, the rotation of the recording member becomes constant and the information can be read accurately.

According to the embodiment of the above (3), if there is an error in reading the information, there is no fear of taking in this information.

According to the above embodiment (4), if there is an error, the information can be read again to read the correct information.

According to the above embodiment (5), it is possible to prevent the information from being read indefinitely when the information is not correctly read.

According to the above embodiment (6), the user can be warned when the operation is stopped.

According to the above embodiment (7), error detection can be performed by a simple method.

According to the information reading device of the above (8), information can be detected in a state where no load is applied other than the rotation of the recording member, and therefore the information can be read accurately.

According to the information reading device of the above (9), there is no fear of sending the film before the end of the information reading.

[0101]

As described above, according to the present invention, it is possible to provide a film information reading device for accurately reading information about a film in a film cartridge.

[Brief description of drawings]

FIG. 1 is a diagram of a main part of a film information reading apparatus according to a first embodiment of the present invention, viewed from the rear surface of a camera body.

FIG. 2 is a view of the main part of the film information reading apparatus of the first embodiment as viewed from above.

FIG. 3 is an external perspective view showing a film cartridge used in a camera to which the film information reading device of the present invention is applied.

FIG. 4 is a cross-sectional view of essential parts of the film cartridge shown in FIG.

5 is a front view showing a state in which a film is pulled out from the film cartridge shown in FIG.

FIG. 6 is an electric circuit diagram showing a control circuit in the film information reading apparatus of the first embodiment.

FIG. 7 is a flow chart showing an operation of the film information reading apparatus in the first embodiment.

FIG. 8 is a flowchart showing a start bit detection subroutine in the film information reading apparatus of the first embodiment.

FIG. 9 is a flowchart showing a subroutine for setting a time judgment reference (TTH determination) of another bit following the start bit in the film information reading apparatus of the first embodiment.

FIG. 10 is a flowchart showing a bar code reading subroutine in the film information reading apparatus of the first embodiment.

FIG. 11 is a timing chart showing changes over time in the drive state of the film feeding motor and the state of the input terminal C3 of the CPU in the barcode reading sequence in the film information reading apparatus of the first embodiment. .

FIG. 12 is a flow chart showing an operation of the film information reading apparatus in the second embodiment of the present invention.

[Explanation of symbols]

 1 Film Case 2 Spool 3 Information Recording Disk 4 Start Bit 6 Film 10-12 Square Hole 20 Fork 21 Photo Reflector 22 Camera Spool 23 Film Feed Motor 24 Switching Mechanism 25, 26 Transmission Mechanism 30 Photo Interrupter

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Akira Inoue 2-43-2 Hatagaya, Shibuya-ku, Tokyo Inside Olympus Optical Co., Ltd.

Claims (3)

[Claims] 1. A camera using a film cartridge having a recording disk that rotates integrally with a spool in a film cartridge and records information relating to the film in a symbolized manner, wherein the recording is performed as the recording disk rotates. Information reading means for reading information about the film recorded on the disk, motor driving means for rotating the spool in the film cartridge in a direction opposite to the film feeding direction, and the film cartridge loaded in the camera. An information reading control unit that controls reading of information related to the film by the information reading unit while detecting that the film is fed and rotating in a direction opposite to the film feeding direction by the motor driving unit. Characteristic film information reading device. 2. The information reading control means keeps the driving voltage of the motor driving means constant while the information reading means is reading information. Film information reader. 3. The information reading control means measures the pulse width of the start bit at the time of reading the start bit, and sets the information reading standard for setting the time judgment standard of the information following the start bit from this pulse width. The film information reading apparatus according to claim 1, further comprising means.