JPH10282537A - Bar code reader for camera, brownie film and film information identification system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To accurately identify a bar code recorded on the joining tape of a Brownie film. SOLUTION: A reflective photosensor 22 is provided to be confronted to the splicing tape 11 as a recording surface for the bar code 12. After a film is loaded, a CPU 24 monitors the output level of a photoelectric signal from the photosensor 22 during the feeding period of the film, to detect the arrival of the joining tape 11. the output level of the photoelectric signal is fluctuated when white and black bars constituting the bar code 12 cross the photosensor 22. The peaks of the fluctuations are monitored by the CPU 24 one by one, the arithmetic means of a pair if maximum and minimum peak values is obtained to set a threshold and the boundary of the next read white and black bars is identified by the threshold.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bar code reader for a camera for reading a bar code recorded on a bonding tape of a brownie film, a brownie film having a bar code recorded on the bonding tape, and the bar code reader and the brownie. The present invention relates to a film information identification system including a combination with a film.

[0002] Brownie films have a size of 120, depending on the form of light-shielding paper used with the film strip.
There are 220 types. In the 120 type, a light-shielding paper is used as a backing paper over the entire film strip, and a leader portion and a trailer portion are continuously provided at both ends of the light-shielding paper. These leader and trailer sections are wrapped around the outer periphery when the film strip is wound around the spool together with the backing paper after unused or after use, so that the film strip is not covered with external light. I have. Also, 2
In the case of the 20 type, the back paper portion of the 120 type is omitted, and light-shielding paper corresponding to the above-described leader and trailer portions is bonded to the leading end and the trailing end of the film strip, respectively.

[0003] These brownie films include, in addition to the 120 and 220 film types described above, monochrome and monochromatic films.
Color negative, reversal type, ISO sensitivity, and 1
For the 20 types, various types are prepared, such as a standard length and a half size of half the length. When a film is loaded in the camera, the position of the pressure plate and the film counter are switched according to the type and type of the film, and the ISO sensitivity is set.

In order to simplify or automate the setting operation of a camera using such a brownie film,
Record a barcode that indicates the type of brownie film on the surface of the bonding tape that joins the leading end of the film strip to the light-shielding paper so that it can be read by the reflective photosensor built into the camera. Has been proposed in Japanese Patent Application No. 7-235127. In a camera suitable for such a bar code system, a film is loaded into the camera, the back cover is closed, a feed motor is activated when a power switch or a shutter button is turned on, and the first frame of the film strip is turned on. The barcode is configured to be read during an initial feed period until the eyes are set behind the aperture.

[0005] A bar code is formed by alternately arranging white bars and black bars, and each bar has two types, thick and thin. The dimensions of the bonding tape used for the brownie film are determined by ISO standards, and the width (length in the feeding direction) is about 25 mm. Therefore, when this bonding tape is used as a barcode recording surface, its recording range is naturally limited, and when the number of barcodes is determined according to the required information amount, the maximum width of the narrow bar is also determined. The terms white bar and black bar are used in the sense that they can be detected as a high-reflection bar and a low-reflection bar based on a photoelectric signal from a reflection-type photosensor. It does not mean.

In order to enhance the accuracy of bar code reading, the width of the thick bar is set to about 2.5 times the width of the thin bar, and the leading and trailing ends have a width of 4 to 5 times the width of the thin bar. Is set, the maximum width of the narrow bar is about 0.8 mm for 13 barcode arrays. Also, when recording a barcode on the bonding tape, since the reflectance of the bonding tape is higher than that of the light-shielding paper, only the black bar is recorded on the surface of the bonding tape with black ink, and the white bar is the bonding tape itself. The surface of the ground can be used.

[0007]

In the above bar code system, the reflection density of the white bar and the black bar on the bonding tape is constant, and the difference between them is sufficiently large. It is assumed that the reference clock pulse to be obtained is stably obtained. However, since the reflectivity of the bonding tape is actually different for each film maker, even if a black bar with a certain reflectivity or less is recorded on the surface, the amplitude of the photoelectric signal obtained from the photo sensor is uniform. No. Therefore, if the threshold value for discriminating between the white bar and the black bar is set to a constant value, there arises a problem that accurate discrimination cannot be performed depending on the type of the joining tape.

Further, since the brownie film is used by being wound around a spool, the winding extends to the joining tape, and the joining tape has curl behavior. Therefore, when the bonding tape passes over the photosensor, the distance between the barcode recording surface and the photosensor is 1 mm at the maximum.
The degree fluctuates, and the photoelectric signal obtained from the photosensor fluctuates as a whole. For this reason, even if the reflectivity of the white bar and the black bar can be controlled to a constant value,
If the threshold is fixed to a constant value, a reading error may occur. In particular, in the present invention, after loading the brownie film into the camera, the barcode is read while the film is being fed, so that the handling of a reading error becomes complicated. There are circumstances that require identification.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an object of the present invention is to provide a white bar and a black bar even when a photoelectric signal obtained from a photo sensor for reading a bar code fluctuates due to various factors. And to accurately discriminate between the two. That is, the bar code reading device built into the camera is improved, and a brownie film in which a bar code suitable for this is recorded is provided.Furthermore, data representing the type of the film can be easily and accurately represented by a combination thereof. It is possible to provide a film information identification system in which even if a brownie film in which a bar code is not recorded and which can be identified on the camera side is loaded, the camera side can use it for photographing without inconvenience. This is the main object of the present invention.

[0010]

SUMMARY OF THE INVENTION In order to achieve the above object, according to the present invention, a bar code consisting of a white bar and a black bar arranged on the surface of a bonding tape is read by a reflection type photo sensor, and the camera is provided with a camera. By comparing the output level of the photoelectric signal with the initial threshold value stored in advance in the built-in storage means, it is detected that the bonding tape has moved to the photo sensor. The initial threshold is individually adjusted to an appropriate value during the manufacture of the camera and is preferably stored in an EEPROM. This initial threshold is set to a value that can discriminate the difference in reflection density between the light-shielding paper and the bonding tape, but since the light-shielding paper is generally colored black with carbon black regardless of the film maker, Differences in reflection density can be easily identified.

Thereafter, reading of the bar code is started. At the time of reading the bar code, a threshold value for identifying a boundary between the white bar and the black bar is set to an output level of the previously read white bar or black bar. It is configured to change according to the maximum value and the minimum value of. Thus, even if the distance between the photosensor and the barcode recording surface changes due to the curling behavior of the film, or the photoelectric signal fluctuates due to the variation in the reflection density itself of the white bar and the black bar, the threshold is set to these values. Can be followed according to the fluctuation of the bar code, and accurate bar code reading can be guaranteed.

If the bar code is not read during the predetermined film feeding period after the bonding tape is detected by the photo sensor, a conventional brownie film having no bar code recorded thereon is loaded based on the reading. From this, it is possible to use the image as it is by displaying a message prompting the same operation as before.

In the brownie film improved according to the present invention, the ground surface itself of the bonding tape is used as a white bar area. For this reason, black bars having a lower reflection density than the ground of the bonding tape are discretely arranged and recorded in the film feeding direction on the bonding tape, and the black bars and the white bar formed of the bonding tape between the black bars are recorded. A bar code is composed of the bar. On the head side of the barcode, a start quiet zone having a width of 3 to 5 mm, which is wider than any barcode element, is provided at the head of the joining tape, and the joining tape itself is detected by detecting the start quiet zone. It is possible to accurately identify what has been fed.

The film information identification system of the present invention is constructed by a combination of the above-described bar code reading device and a brownie film, and data corresponding to the type of film strip is automatically input to the camera without error. Even when a brownie film with no code recorded is loaded, it is possible to continue shooting as before.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows the appearance of a brownie camera incorporating a bar code reader of the present invention when the back cover is opened.
FIG. 2 shows a 120 type brownie film used in this camera. When the back cover 2 is opened, a loading chamber 4 and a winding chamber 5 formed in the camera body 3 appear.
This camera is a so-called semi-format camera, and an exposure range of about 6 × 4.5 cm is determined by the exposure frame 6.

As shown in FIG. 2, the 120 film 7 has a film strip 10 wound around a spool 8 together with a light-shielding paper 9, and the light-shielding paper 9 has a backing paper portion 9a of the film strip 10 and a leading end of the film strip 10. Leader 9b extended to the side, and the filmstrip 1
And a trailer portion extending to the rear end side from zero. When the reader strip 9b is wound around the upper layer when not in use, the film strip 10 is not fogged by external light. Also, when shooting, use it while wrapping it around another spool from the leader part side, and eventually the trailer part will be wrapped around the upper layer side,
Also, the photographed filmstrip 10 is not fogged by external light.

The length of the film strip 10 is 120
In case of type, two types are prepared. The normal size is a length capable of taking 12 frames when photographing with a screen size of 6 × 6 cm, and the half size is a length capable of taking 6 frames. In the semi-format camera shown in FIG.
Since the screen size is 5 cm, the normal size is 1
With 6 frames and half size, 8 frames can be shot.

The 220 type is the backing paper 9 of the light-shielding paper 9.
a is omitted, and a leader portion and a trailer portion of the light-shielding paper 9 are joined to the leading end and the trailing end of the film strip 10, respectively. Since there is no backing portion 9a, when the spool 8 is wound around the same winding diameter as 120 films, the length of the film strip becomes almost double, and the number of frames taken per film is 32 in normal size. Note that 22
Type 0 has only normal size and no half size.

In both cases 120 and 220, the leading end side of the film strip 10 is joined to the light-shielding paper 9 by a joining tape 11. In the brownie film of the present invention, the bonding tape 11 is used as a barcode recording surface, and a barcode 12 is recorded according to a format as shown in FIG. The joining tape 11 is made of synthetic paper, and the background color of its surface is white. Therefore, two kinds of black bars of wide width / narrow width are spread on the surface.
By arranging them at two narrow intervals, a bar code 12 in which black bars and white bars are alternately arranged can be obtained.

As shown by the bit numbers (1) to (13) in FIG. 3, a 13-bit bar code is formed by printing seven black bars on the surface of the bonding tape 11 by, for example, thermal transfer recording. A start quiet zone 14 and an end quiet zone 15 having a fixed width are secured at the leading side (left side in the figure) and the rear end side of the bar code. It consists of the surface of the earth. Joining tape 11
In consideration of the width (length in the feeding direction) of 25 mm, the width of the narrow element of the white bar or the black bar is about 0.8 mm, and the width of the wide element is 2. It is determined to be about five times.

The width of the start quiet zone 14 is determined by the distance between the front edge of the joining tape 11 and the edge of the first black bar, and its value is set to be larger than the wide element of the white bar or black bar. It is set in the range of ± 1 mm. If the width is reduced to about 2 mm or less, the leading edge of the joining tape 11 and the first black bar of the bar code are too close to each other, and the start quiet zone 1
The reflected light from 4 decreases before reaching a sufficiently high level, and an error easily occurs in reading by the photo sensor.

That is, if the photo sensor has started a bar code reading sequence, for example, 1 m
Although the start quiet zone of about m is sufficient for identification, after the start of film feeding, the CPU that manages the sequence of the entire camera checks the set state of various switches or actuators and performs various sequences. Since the program initialization processing is performed, it is difficult to perform a barcode reading sequence that imposes a heavy burden on software processing in parallel with this, and detection of the start quiet zone 14 with sufficient resolution is not possible. It is not possible.

Therefore, whether or not the joining tape 11 has been moved is monitored at a coarse cycle every film feed length of about 1 to 2 mm, and a bar code reading sequence is started after the movement is detected. However, if the start quiet zone 14 is 2 mm or less as described above, a sufficient reflected light may not be obtained from the start quiet zone 14 due to a difference in timing from the monitoring period. A detection error occurs. In order to avoid this problem, it has been confirmed that it is effective to set the width of the start quiet zone 14 to 3 mm or more, which is sufficiently long with respect to the monitoring cycle of the bonding tape, as described above.

If the width of the start quiet zone 14 is too large, the narrow bar is about 0.8 mm and the thick bar is about 2.5 times the 13-bit bar within the limited width of the joining tape 11. Since the code 12 cannot be recorded, the distance is set to 5 mm or less in consideration of a positional deviation when printing a barcode. In addition, the end quiet zone 15 is set to at least 2 mm or more.

Since a photo sensor for reading a bar code is of a reflection type, it is necessary that there is a difference between the reflection densities of the white bar and the black bar. Bar reflectance is low. Also,
When light for reading is emitted from a reflection type photo sensor, if the light is specularly reflected on the surface of the black bar, the reflection density of the black bar increases, making it difficult to distinguish it from the white bar. . Therefore, the reflectance of the ground (white bar) of the bonding tape 11 with respect to the light for reading is set to 50% or more, its glossiness is suppressed to 35% or less, and the reflectance of the black bar is set to 3%.
It is preferable that the glossiness is controlled to 20% or less by setting the glossiness to 0% or less. As will be described later, the bar code reading photosensor is used at an angle, and the reading is performed by using the diffuse reflection light from the bar code recording surface, thereby enabling highly accurate identification.

In the code data, for each of the white bar and the black bar, the narrow-width element represents data "0" and the wide-width element represents data "1". 120 in first 3 bits
/ 220 and the film size are assigned.
As described above, the 120 film has a normal size and a half size, and the 220 film has only a normal size. Consequently, the first three bits represent three types of information. Originally it is a redundant assignment.

However, in the present system, a reference length DX for identifying a wide / narrow element is set based on the first three bits of data.
For this reason, the first three bits are limited to use only one wide element, and the data length of three bits is kept constant. Then, after measuring the data length DL of the three bits, DX is calculated as DX = DL × (35/90), and a shorter element than DX is used as a narrow element, and an element longer than DX is used as a wide element. Identify as The data length DL and the reference length DX are not mechanical lengths but are actually counts of motor rotation pulses obtained in synchronization with rotation of the feed motor.

Since the curl behavior of the joining tape 11 is remarkable from the center to the rear end of the joining tape 11, the reference length DX is set by the first three bits as described above. It can be determined more accurately, and it has been confirmed that there is no problem in practice. Moreover, the data of these three bits is 120/220.
Is also used as information indicating the type and film size of the
Since there is no restriction on the subsequent 10-bit data, a reasonable bar code system can be obtained in total. And the bit number (4)
The combination of the film type (monochrome / color reversal / color negative) and the ISO sensitivity is expressed by the 10 bits of (13).

An engaging hole 9c provided at the tip of the leader 9b is used when the leader 9b is engaged with an empty spool 13 set in the winding chamber 5. For this reason, a locking claw 13b is provided behind the slit 13a of the spool 13, and when the leading end of the leader portion 9b is inserted into the slit 13a when the film is loaded, the locking claw 9c and the locking claw 1 are formed.
3b is engaged. Therefore, after that, when the feed motor is driven by the closing signal of the back cover 2 to rotate the spool 13, the film feeding is automatically started.

Although some film makers do not have the above-mentioned locking holes 9c and locking claws 13b, some films and spools are not provided. In such a case, after inserting the tip of the leader 9b into the slit 13a, the dial 17 is operated. Then, the leader portion 9b is wound around the spool 13 two or three times. Thereafter, the back cover 2 is closed and the feed motor is driven to start the film feed in the same manner. It is to be noted that the setting position of the pressure plate 18 is switched before the back cover 2 is closed, depending on whether the film to be used is 120 or 220. When the back cover 2 is closed, the set position of the pressure plate 18 is detected by a sensor pin on the camera body side, and the film counter is switched accordingly.

A sensor section 20 is provided on a film guide surface between the exposure frame 6 and the loading chamber 4. As shown in FIG. 4, a reflection type photosensor 22 is incorporated in the sensor section 20, and a mask plate 23 is provided on the front surface thereof.
A slit having a width of about 0.6 mm narrower than the narrow element of the bar code 12 is formed in the mask plate 23, and the photo sensor 22 emits and receives light for reading through this slit. The light for reading has a wavelength range (900 to 950 nm) that does not expose the filmstrip 10. When the photo sensor 22 is used only for reading the bar code 12 recorded on the joining tape 11, the sensor unit 20 may be provided between the exposure frame 6 and the winding chamber 5.

The photo sensor 22 is inclined with respect to the light-shielding paper 9 and the feeding surface of the filmstrip 10 so as not to be affected by the specularly reflected light. The tilt direction is a direction along a plane orthogonal to the film feeding direction, that is, a direction in which the photo sensor 22 is tilted up and down around a horizontal axis when the feeding surface is vertical, and the angle is Is preferably around 20 °.

When a signal for closing the back cover 2 is input to the CPU 24, the feed motor 26 is driven via the motor driver 25, and the spool 13 is rotated in the winding direction via the speed reduction mechanism 27. When the feeding motor 26 rotates, an encoding plate 28 having a large number of slits formed radially at a constant angular pitch rotates. A photo interrupter 29 is provided so as to sandwich the encoding plate 28, and a motor rotation pulse synchronized with the rotation of the feeding motor 26 is generated from the photo interrupter 29 and input to the CPU 24.

The photo sensor 22 outputs a photoelectric signal corresponding to the amount of diffuse reflection of each of the light-shielding paper 9, the bonding tape 11, and the film strip 10 passing through the sensor section 20 after the start of film feeding. . This photoelectric signal is input to the CPU 24 via the waveform shaping circuit 30. The waveform shaping circuit 30 functions to remove a spike-like pulse superimposed on the photoelectric signal due to the influence of noise.

As shown in FIG. 1, a driven roller 32 is provided between the exposure frame 6 and the winding chamber 5, and when the film feeding is started, the light-shielding paper 9, the joining tape 11, and the film strip 10 are moved. It follows and rotates. Driven roller 32
The same encoding plate 33 as the encoding plate 28
Has been fixed. A photo interrupter 34 is provided so as to sandwich the encoding plate 33, and the encoding plate 3
By the rotation of 3, the photo interrupter 34 outputs a film feeding pulse synchronized with the feeding, and inputs the pulse to the CPU 24. If the rotation of the driven roller 24 is within a range in which a large load is not applied, for example, the driven roller 24
The gear plate 25 may be engaged with a speed increasing gear having a reduced gear ratio, and the encoding plate 25 may be rotated by the speed increasing gear. As a result, a film feed pulse can be obtained at a finer cycle.

A ROM 36, a RAM 37, and an EEPROM 38 are used for a barcode reading process described later, and data is exchanged with the CPU 24. R
The OM 36 stores a sequence program for reading barcodes and a data table for decoding film information from the read barcode data. RA
M37 is used to temporarily store and store flags and data obtained during the execution of the sequence program, and these data are read by the CPU 24 as needed during the execution of the sequence program.

An initial threshold value S used to detect whether or not the joining tape 11 has moved to the sensor unit 20 after the start of the film feeding is written in the EEPROM 38. The value of the initial threshold value S varies depending on the sensitivity of the photo sensor 22 incorporated in the sensor unit 20.
Adjusted for each camera. The EEPROM 38 further stores two types of pulse numbers “K” and “Q” to be collated in a bar code reading process and a feeding process, which will be described later.
The final threshold value SX is written.

Hereinafter, the operation of the present invention will be described. FIG. 5 schematically shows the main flow, in which the joining tape 11 is used based on a photoelectric signal obtained from the photo sensor 22.
Is detected, and then the bar code 12 is detected.
For those provided with, barcode reading and code data identification are performed.

The first frame setting process is performed by stopping the driving of the feeding motor 26 at the time when feeding of a predetermined length is performed based on the timing at which the joining tape 11 is detected. The dimension length of the joining tape 11 is I
Since it is standardized by SO, the first frame of the filmstrip 10 can be set behind the exposure frame 6 by the above processing. This first frame setting process can be performed regardless of the presence or absence of the barcode 12.

After the first frame setting process is completed, the normal photographing standby state is maintained as before, so that the feeding motor 26 is automatically automatically operated each time a photographing operation is performed.
Is driven to feed one frame of film, so that the shooting can be sequentially repeated. When it is confirmed by the film counter that the photographing of the last frame has been completed, the last film feed is started.

During this feeding period, the filmstrip 1
It is detected that the trailing end of the sheet 0 has passed the sensor section 20, and the trailer section of the light-shielding paper 9 is fed from that point. Since the length of the trailer section is also set within a certain range by the ISO, if the feed motor 26 is automatically stopped after a lapse of time according to the length, the brownie film including the trailer section is put on the spool 13 including the trailer section. Are all wound up, and the back cover 2 can be opened immediately. Further, since the film feed pulse FP is interrupted when the trailer unit is wound on the spool 13, the stop timing of the feed motor 26 may be determined based on this.

The procedure for reading a bar code will be described with reference to FIGS. Back cover switch (SW)
Switches from off to on when the back cover 2 is locked in the closed position. In response to the ON signal, the CPU 24 issues a feed start command to the motor driver 25, and the feed motor 26 starts driving. The spool 13 starts rotating via the speed reduction mechanism 27, and first, the leader 9 b of the light-shielding paper 9 is wound on the spool 13.

When the feed motor 26 is driven, a motor rotation pulse MP is input from the photo interrupter 29 to the CPU 24. Further, the driven roller 32 rotates with the feeding of the light-shielding paper 9, and a film feeding pulse FP is input from the photo interrupter 34 to the CPU 24. The film feeding pulse FP is used to detect the actual feeding length of the light-shielding paper 9 and the film strip 10 as accurately as possible, and the motor rotation pulse MP detects the feeding length of the light-shielding paper 9 and the film strip 10 as finely as possible. It is used for the purpose of doing.

The rotation of the driven roller 32 is sufficiently increased by using a speed-up gear or the like to increase the number of film feed pulses FP obtained per unit rotation of the driven roller 32. The subsequent processing can be performed only by the film feeding pulse FP without using the above. However, when a speed-increasing gear or the like is connected to the driven roller 32, the rotational load of the driven roller 32 is increased, and the driven roller 32 cannot be rotated smoothly, so that the driven roller 32 and the light-shielding paper 9 or the film strip 10 cannot be rotated. Slip occurs during the time, and it becomes impossible to measure the feed length accurately.
Therefore, as described above, two types of pulses, that is, the film feeding pulse FP and the motor rotation pulse MP are used, so that the encoding plates 28 and 33 and the photo interrupters 29 and 34 do not need to be too expensive. However, the feed length can be measured with sufficiently high accuracy.

As shown in FIG. 7, step 1 (ST1)
When it is confirmed that the back cover switch is turned on, the EEPRO
The initial threshold value S is read from M38, and this is the threshold value S0. The value of the initial threshold value S is determined based on the diffuse reflection density of the ground surface of the bonding tape 11 and in consideration of the sensitivity of the photosensor 22. The reflection density of the bonding tape 11 is higher than the reflection density of the light-shielding paper 9 regardless of the film maker. Good.

After setting the threshold value S0, the driving of the feeding motor 26 is started, and the film is fed. Feed motor 26
The motor rotation pulse MP is input to the CPU 24 in synchronization with the driving of the motor, and the film feeding pulse FP is input to the CPU 24 in synchronization with the rotation of the driven roller 32. The output level PLV of the photoelectric signal is monitored at the same time as the film is fed, but the CPU 24 keeps monitoring the photoelectric level until the film feed pulse FP input from the photo interrupter 34 reaches the number of pulses “K” written in the EEPROM 38. The reading of the signal output level PLV is invalidated (ST2).

The value of the number of pulses "K" is set to a value of about 20 to 30 when, for example, one film feed pulse FP is obtained for every film feed length of 1.225 mm. By invalidating the reading of the photoelectric signal output level PLV for a certain period immediately after the start of the feed motor 26 by the pulse number “K”, the output level PLV in which the feed is unstable and noise is likely to be superimposed can be ignored. .

As long as a normal operation is performed, after the back cover 2 is closed, when the film is fed by the number K of film feeding pulses FP, the sensor unit 20 is provided with the leader of the light-shielding paper 9. The unit 9b faces, and the value of the output level PLV is always lower than the threshold value S0. Therefore, if the output level PLV at this time is larger than the threshold value S0, it means that an abnormal operation such as opening and closing the back cover 2 during the photographing is performed, and in this case, the peak value pk0 is forcibly set to the initial threshold value S (ST
3).

When the value of the peak value pk0 is set to a low value in this way, the threshold value used to determine the boundary between the white bar and the black bar is forcibly set to a low value as described later. As a result, even if the output level PLV due to the reflected light from the filmstrip 10 fluctuates finely due to the influence of noise or the like, this is not recognized as a barcode, and erroneous reading of the barcode during abnormal operation can be avoided. . As for the motor rotation pulse MP, for example, if one motor rotation pulse MP can be obtained for every 0.125 mm of the film feeding length, a bar code having a narrow element width of about 0.8 mm can be used in practical use. It is possible to identify with a problem-free resolution.

When the film feeding pulse FP reaches "K",
After the process of ST3 is performed as necessary, the count value of the film feeding pulse FP is cleared, and the output level PL is set.
The value of V is monitored again by the CPU 24. In this monitoring process, the reader unit 9 of the light-shielding paper 9
b passes through the output level P as shown in FIG.
LV fluctuates slightly at low levels. And CPU2
4 updates the lowest value of the output level PLV as the peak value pk0 during this period (ST4).

When the joining tape 11 moves above the sensor section 20 by continuing the feeding, the output level PLV increases because the start quiet zone 14 is provided on the leading edge side of the joining tape 11. . Then, "PL
When V> S0 ”(ST5), the CPU 24 detects that the bonding tape 11 has moved to the sensor unit 20. At the same time, “N = 1” is set, and FIG.
As shown in (2), the counting of the film feeding pulse FP is restarted, and the counting of the motor rotation pulse MP is started.

The monitoring of the output level PLV until the start quiet zone 14 of the joining tape 11 is detected is as follows.
It is performed in a cycle of every 1.225 mm of the film feeding length in synchronization with the generation of the film feeding pulse FP.
mm start quiet zone 14 is the sensor section 20
, A bar code reading sequence is started, and the output level PLV is monitored at a fine cycle in synchronization with the motor feed pulse MP.

The start quiet zone 14 passes through the sensor section 20, and when the first black bar moves, the output level PLV decreases. The CPU 24 monitors the change of the output level PLV at this time, and
It is determined that there is a maximum value when V drops by a predetermined level width, the maximum value before the effect of the predetermined level width is held, and the value is stored as a peak value pk1 (ST6-
ST7). For this storage, a predetermined address area prepared in advance in the RAM 37 is used.

Here, the bar code 12 is attached to the joining tape 11.
Is not recorded, the output level PLV remains almost constant. Then, when the count value of the film feeding pulse FP reaches １ ／ of the pulse number W corresponding to the width of the bonding tape 11 (ST8), the CPU
Reference numeral 24 identifies a bonded tape on which the barcode 12 is not recorded, and the process proceeds to the first frame setting process (ST9). Of course, this processing is "N
= 1 ”.

The joining tape 1 provided with the bar code 12
For 1, the barcode 12 is read.
The reading of the bar code 12 is performed by reading how many of the elements of the white bar and the black bar are the motor rotation pulses MP. At this time, the threshold value SN is used to identify the boundary between the white bar and the black bar, and the value of the threshold value SN is determined by two peak values (maximum value and minimum value) of the output level PLV detected immediately before. I can decide.

That is, the threshold value S1 for detecting the front edge of the first black bar is an arithmetic mean of the peak value pk0 obtained first as the minimum value and the peak value pk1 obtained as the next maximum value. (ST10). In the flowchart of FIG. 8, the respective peak values of the local maximum value and the local minimum value are identified and shared in ST10, and the threshold value S
Although N is calculated as the arithmetic mean value, it is also possible to adopt a procedure in which the local maximum value and the local minimum value are individually identified, and the local maximum value and the local minimum value are updated, respectively. .

Similarly, the threshold value S2 for detecting the trailing edge of the first black bar is determined based on the peak values pk1 and pk2. Then, the output level PLV becomes equal to the peak value pk.
From the point in time when the threshold value S1 decreases from 1 (maximum value),
The count value (MP value) of the motor rotation pulse MP counted from the peak value pk2 (minimum value) to the time point when the threshold value S2 is reached is written into the data memory (1) as the first black bar width data. (ST11). In addition,
The width data of the quiet zone 15 is written in the data memory (0), but is not used for identifying the barcode itself.

As described above, by sequentially updating the threshold value SN, the width data of the barcode element can be accurately read without being greatly affected by the fluctuation of the output level PLV due to the curl behavior of the joining tape 11. It becomes possible. In order to prevent the threshold value from extremely changing due to a peculiar value due to contamination of the bonding tape 11, the threshold value is set based on the average value of the maximum value and the minimum value measured immediately before, The threshold value may be set by averaging the local maximum value and local minimum value of the previous two times.

Since the bar code 12 has a 13-bit configuration, the bar code reading process is repeatedly performed until “N = 14” is reached.
Is updated. As a result, the bonding tape 11 has a curl characteristic, and therefore, the output level PLV of the photoelectric signal
May vary, the boundary between the white bar and the black bar can be accurately identified, and the barcode reading accuracy can be significantly improved.

ST12 is for shifting to error processing when the 13-bit bar code 12 is not within the predetermined length range. That is, an error occurs when the count value of the film feeding pulse FP has reached the pulse number “W” corresponding to the width of the bonding tape 11 but the detection of the 13-bit barcode element has not yet been completed. . In this error processing, for example, an error is displayed on a liquid crystal display unit or the like incorporated in the camera to urge the user to manually input various film information settings required for shooting.

When the 13-bit data is properly obtained, the code data identification process in ST13 is performed. The identification process of the code data is performed according to the procedure shown in the flowchart of FIG. First, the CPU 24 reads the width data from the data memories (1) to (3) and adds them (ST14), and the data length D of the first 3 bits is read.
Find L. Subsequently, the reference length DX is calculated in ST15. This reference length DX corresponds to the data memory (1) to
This becomes a reference for identifying whether the width data written in (13) corresponds to a wide element or a narrow element.

After the reference length DX is obtained in this way, each width data of the data memories (1) to (13) is sequentially compared with the reference length DX, and stored in the code memories (1) to (13) by the processing of ST16. Code data “0” and “1” are written. Then, the data for decoding the film information stored in the ROM 37 is referred to, and the code memories (1) to
According to the code data of (3), the film type and the film size of 120/220 and the code memories (4) to (1)
The film type of monochrome / color reversal / color negative and ISO sensitivity are identified by the code data of 3) (ST17).

Of the film information thus identified,
The 120/220 film type and film size information can be used for adjusting the film counter of the camera, and when the function of automatically switching the pressure plate 18 is incorporated in the camera, it is used as the switching information. Can be. As described above, in the case where the back cover 2 is opened to set the pressure plate 18 and the film counter is adjusted in conjunction with this, the setting position of the pressure plate 18 is appropriate based on the information obtained from the barcode. It can be used to check if there is. The ISO sensitivity is input to an exposure control circuit of the camera as an exposure control factor, and a combination of the above-described bar code reading device and a brownie film with a bar code provides a rational film information identification system.

After the front edge of the joining tape 11 is detected by the threshold value S0, the CPU 24 continues counting the film feeding pulses FP, and the first frame setting process is performed based on the count value. . For this reason, the CPU 24 sets the film feeding pulse FP
It is monitored whether or not the counted number has reached "Q", and when the counted number has reached "Q", the drive of the feed motor 26 is stopped (ST9). As described above, the bonding tape 11
Since the length in the feeding direction is determined by ISO to be within a predetermined range, if the value of “Q” is determined according to the length, the first frame just behind the exposure frame 6 can be obtained. The eyes can be stopped. In this state, the photo sensor 22 outputs a photoelectric signal corresponding to the amount of light reflected from the filmstrip 10.

When the first frame set is completed in this way, the count value of the film feeding pulse FP is cleared, and the first frame is set in a photographing standby state. When the photographing operation is performed, after receiving the exposure completion signal, the CPU 24 drives the feed motor 26 to feed the film one frame. At the same time, the driven roller 32 rotates, and a film feed pulse FP is similarly obtained from the photo interrupter 34. This is counted again, and when the count value corresponding to one frame of the film is reached, the feed motor 26 is turned on. Driving may be stopped.

When the photographing of the last frame is completed, the feed motor 26 is driven to feed the final film. The final film feeding is performed until the light shielding paper 9 is completely wound on the spool 13 up to the trailer portion. Even if the photographing is completed in the last frame, the photo sensor 2 is usually provided after the start of feeding because the film strip 10 has a margin.
Numeral 2 detects reflected light from the filmstrip 10. Then, when the rear end of the filmstrip 10 has passed, the photo sensor 22 detects the light reflected from the trailer portion of the light-shielding paper 9, and the output level PLV decreases.

Therefore, the final threshold SX lower than the reflection density of the film strip 10 and higher than the reflection density of the light-shielding paper 9 is written in the EEPROM 38, and the final film feeding is performed while comparing the output level PLV with the final threshold SX. Is performed, the filmstrip 10 is
0 can be confirmed. Then, the feed motor 26 is stopped after a prescribed feed period according to the length of the trailer section from that time, or when the film feed pulse FP is no longer output after the above confirmation is performed, the feed is stopped. When the feed motor 26 is stopped, all of the brownie film, including the trailer, is spooled.
The stop control of the feed motor 26 can be automatically performed at the time when the feed motor 26 is wound.

[0068]

As described above, according to the bar code reader of the present invention, a bar code recorded on a bonding tape of a brownie film can be accurately identified without being affected by the curling behavior of the bonding tape. It becomes possible. In addition, since the system detects that the joining tape has moved before reading the barcode, even if a brownie film without a barcode is used, the time when the joining tape is detected is used as a reference. To perform auto-setting of the first frame.

Further, the bonding tape of the brownie film according to the present invention is provided with a start quiet zone of 3 to 5 mm wider than the bar code element at the head side of the bar code. It is possible to reliably recognize that the joining tape has moved without using a reading sequence, and at the same time, record a barcode of about 10 to 15 bits with a margin within a limited width of the joining tape. be able to.

Further, by combining the camera incorporating the barcode reading device of the present invention with the above-mentioned brownie film, it becomes possible to automatically input various kinds of film information necessary for photographing to the camera side. It can be used to omit the setting operation or to check whether the manual setting operation has been performed properly, and it will be a very effective film information identification system for widespread use of brownie cameras in general .

[Brief description of the drawings]

FIG. 1 is a rear side external view of a brownie camera using the present invention.

FIG. 2 is an explanatory diagram of a brownie film (120 type).

FIG. 3 is an explanatory diagram of a barcode.

FIG. 4 is a schematic diagram of a barcode reading device.

FIG. 5 is a flowchart showing the overall processing flow of a brownie camera using the present invention.

FIG. 6 is a timing chart showing a barcode reading operation.

FIG. 7 is a flowchart showing a flow up to a joining tape detection process.

FIG. 8 is a flowchart showing a barcode reading procedure.

FIG. 9 is a flowchart showing a procedure for identifying barcode data.

[Explanation of symbols]

 2 Back Cover 6 Exposure Frame 9 Shielding Paper 10 Film Strip 11 Bonding Tape 12 Bar Code 14 Start Quiet Zone 18 Pressure Plate 20 Sensor Unit 22 Photo Sensor 26 Feed Motor 28,33 Encode Plate 29,34 Photo Interrupter 32 Followed Roller

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Tokuji Sato 3-13-45 Izumi, Asaka-shi, Saitama Prefecture Fuji Photo Film Co., Ltd. (72) Inventor Teruyoshi Makino 210 Nakanuma, Minamiashigara-shi, Kanagawa Fuji Photo Film Co., Ltd Inside

Claims (4)

[Claims] The present invention is applied to a camera using a roll-shaped brownie film in which a leading end of a film strip is joined to a light-shielding paper with a joining tape, and the leading end of the light-shielding paper is locked on a take-up spool. In the process of feeding the film by rotating the take-up spool by driving, a bar code composed of black bars and white bars arranged on the surface of the joining tape is read based on a photoelectric signal obtained from a reflection type photo sensor. In the bar code reading device of the camera, the bar code is read by detecting that the bonding tape has moved to the photo sensor by comparing the initial threshold value stored in the storage unit and the output level of the photoelectric signal. In addition, the threshold for identifying the boundary between the white bar and the black bar at the time of reading the barcode is set to the threshold value of the previously read white bar. Other camera barcode reader being characterized in that so as to change in accordance with the maximum value or the minimum value of the output level of the black bar. 2. The method according to claim 1, wherein the threshold is sequentially set as an arithmetic mean of a pair of a maximum value and a minimum value of the output level of the white bar and the black bar read immediately before. Item 2. A bar code reading device for a camera according to item 1. 3. A film strip, a light-shielding paper provided at least on the leading end side thereof, and a joining tape for joining the leading end of the film strip to the light-shielding paper and having a higher surface reflectance than the light-shielding paper. In the brownie film, on the bonding tape, black bars having a lower reflection density than the ground of the bonding tape are discretely arranged and recorded in the film feeding direction, and these black bars and the ground of the bonding tape between the black bars are recorded. The bar code is composed of a white bar, and the head side of the bar code is formed of a joining tape, and is 3 to 5 mm thicker than any bar code element.
Brownie film with a start quiet zone with a width of 4. A bar code according to claim 3 is set in advance for each type of film strip, and the bar code is read by a bar code reading device according to claim 1 or 2 to correspond to the type of film strip. A film information identification system wherein data is automatically input to a camera.