JPH06111208A - Data reading method and data recording method - Google Patents

Abstract

PURPOSE:To prevent errors in reading by obtaining an average value of the speed when the pulse intervals t1, t2 of reading signals are equal to each other and the changing width of the speed through simulations and transferring a medium so as to satisfy t1<t2. CONSTITUTION:Supposing that the transferring speed changes with a constant cycle while the recording density is a parameter, the relationship between an average value of the transferring speed and the changing width of the speed when the pulse intervals t1=t2 is held is obtained through simulations. The curve representing the relationship has a bending point at the center thereof, starting to incline negatively or considerably small from the bending point. When the average value and the changing width of the transferring speed are increased, the inclination becomes positive and large. In the range where the average value of the transferring speed is smaller than at the bending point and the changing width is within an OK zone, the ratio of pulse intervals of reading signals becomes close to that of the magnetization width. If the transferring distance of a recording medium by half the changing cycle of the transferring speed is set to be smaller than or approximately equal to the shortest length of the magnetic or optical change added to the medium in predetermined direction, the erroneous reading due to the change of the transferring speed is prevented.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an information reading method for reading information recorded on a recording medium and an information recording method for recording information on the recording medium.

[0002]

2. Description of the Related Art In recent years, there has been proposed a system in which information such as print size and photographing conditions is recorded on a photographic film in addition to an image, and the information is read and used effectively when printing is performed. In this system, for example, when recording an image on a photographic film provided with a magnetic recording layer, the information is magnetically recorded by a magnetic head and read at the time of printing, or a bar code or the like representing the information outside the screen is optically recorded at the time of recording. Information is transmitted by physically recording and reading at the time of printing. This makes it possible to automatically print each image frame recorded on photographic film in the size desired by the user, to print for each image frame under the optimal printing conditions according to the shooting conditions, to simplify the charge calculation, It is possible to rationalize and improve the efficiency of work in the photo lab. Further, by recording the ID for identifying the user, the ID of the photo lab, and the like, it is possible to prevent mistakes during collation work and collection / delivery.

By the way, photographic film is often fed frame by frame and processed in image frame units, and in order to position the image frame at a predetermined position, a pulse motor is often applied as a motor for transporting the photographic film. . As is well known, since the pulse motor rotates stepwise for each pulse of the input pulse signal, the transport speed when transporting one frame of photographic film and stopping the transport is shown in FIG. It varies as shown. That is, when the tension applied to the photographic film is unstable, the transport speed V greatly changes with respect to the target transport speed when the transport is started and stopped, and the amplitude of the fluctuation gradually decreases with the passage of time. The fluctuation of the transport speed V continues even if a predetermined time or more has elapsed from the start of transport.

If such a change in the transport speed of the photographic film occurs during information recording or information reading, for example, there is a possibility that the content of information changes. The inconvenience caused by the fluctuation of the transport speed will be described below by taking as an example the case where information consisting of binary data is magnetically recorded on a photographic film and read.

At the time of recording the information, for example, the bit of the value "0" in the information consisting of the binary data is shown in FIG.
Corresponding to the waveform 200 shown in (A), the bit having the value “1” is made to correspond to the waveform 202, and the waveforms 200 and 202 are combined to create the signal 204 representing the information. The waveform 200 rises at the beginning of the cycle T and is 1 /
3 is a waveform that falls when a time T ₁ corresponding to 3 has elapsed, and rises when a time T ₂ that corresponds to ⅔ of the cycle T has elapsed from this falling.
Is a waveform that rises at the beginning of the waveform, falls when the time T ₂ has elapsed, and rises when the time T ₁ has elapsed from the fall.

When the signal 204 is supplied to the recording head while the photographic film is being conveyed, the recording head is moved as shown in FIG.
As shown in FIG. 2 (B), a recording signal 206 having a waveform obtained by differentiating the signal 204 (a waveform in which a pulse is generated at a rising edge and a falling edge) is magnetically recorded, whereby the photographic film is shown in FIG. 12 (C). As described above, the recording signal 206 is magnetized so that the magnetization direction is inverted in the portion where the pulse of the recording signal 206 is generated. When the photographic film magnetized in this way is conveyed and read by the reading head, as shown in FIG.
A read signal 208 is obtained in which a pulse occurs in the portion where the magnetization direction is reversed. Here, when the recording medium is conveyed at a constant speed during information recording and information reading, the ratio of magnetization widths L1: L2
And the pulse interval ratio t ₁ : t ₂ of the read signal 208 is the pulse interval ratio T ₁ : T ₂ (= 1: 1) of the recording signal 206.
2) and the content of information can be accurately judged based on the pulse interval of the read signal 208.

However, as shown in FIG. 13, when the transport speed at the time of recording information changes as shown in FIG. 13B with respect to the recording signal 206 shown in FIG. Changes along the length (Fig. 13 (C))
reference). That is, pulse 210A and pulse 210B
The lengthwise dimension of the magnetized portion 212A caused by the photographic film transport speed V is determined by the pulse 210A and the pulse 210B.
13B corresponds to the result of integration in the section corresponding to the recording timing interval, that is, the area L1 ′ shown in FIG. Similarly, the linear dimension of the magnetized portion 212B caused by the pulses 210B, 210C is such that
This corresponds to the result (area L2 ′) of integration in the section corresponding to the recording timing intervals of 10B and 210C. The same applies to the other magnetized portions.

Therefore, even if the photographic film magnetized as described above is conveyed at a constant speed and information is read by the read head, the pulse interval of the read signal 208 is t ₁ ': as shown in FIG. _{t 2 '= L1': L2} '≠ T 1: T 2 t 1 ": t 2" = L1 ": L2" ≠ T 1: T 2 , and the read error is judged by mistake the value of each bit is generated There is fear.

Even if the photographic film is conveyed at a constant speed and magnetized at a ratio L1: L2 of the magnetization widths of exactly 1: 2 as shown in FIG.
When the transport speed changes as shown in FIG. 14, the pulse interval of the read signal 208 changes as shown in FIG. That is, when the conveying speed is low, for example, when the magnetized portion 212A is being conveyed, it takes time to convey the photographic film by the distance L1, and the interval between the corresponding pulses 214A and 214B of the read signal 208 becomes long. Further, when the transport speed is high, for example, when transporting the magnetized portion 212B, the transport of the distance L2 of the photographic film is completed in a short time, and the interval between the corresponding pulses 214B and 214C of the read signal becomes short. Therefore, a reading error may occur.

The above problem similarly occurs when information is optically recorded on a photographic film by a bar code or the like. Therefore, conventionally, a photographic film is conveyed by using a high-precision motor with extremely small speed fluctuation, or the inertial mass of the rotating shaft is increased by attaching a so-called inertia to the rotating shaft of the motor to increase the photographic film. The amount of fluctuation in the transport speed of was reduced.

[0011]

However, in recent years, there has been an increasing demand for miniaturization of photo processing devices,
It is not preferable to use a high-precision motor that tends to be large. Further, when recording information on a photographic film with a camera, it is difficult to mount the large-sized high-precision motor in consideration of portability of the camera. Furthermore, in frame-by-frame transport of photographic film, the transport speed rises and falls instantly at the start and stop of transport, and the accuracy of the stop position is required to be high. However, there is a problem that the fall and stop accuracy are adversely affected.

The present invention has been made in view of the above facts, and an object of the present invention is to obtain an information reading method and an information recording method capable of preventing the occurrence of a reading error due to a change in the conveyance speed.

[0013]

In order to achieve the above object, the invention according to claim 1 conveys a recording medium along a predetermined direction, and a predetermined recording density is given to the recording medium. An information reading method for reading the predetermined information by detecting a magnetic or optical change that represents information, and an average value of a transport speed of a recording medium for correctly reading the information with respect to the predetermined recording density. It is characterized in that the relationship with the fluctuation range of the transport speed is obtained in advance, and the recording medium is transported to read the information so that the information can be correctly read based on the relationship.

Further, the distance for carrying the recording medium in a half cycle of the fluctuation cycle of the carrying speed of the recording medium is the shortest length along a predetermined direction of the magnetic or optical change given to the recording medium. It is preferable that the recording medium is conveyed so that the information is read so as to be smaller or substantially equal to the above.

Further, the distance for carrying the recording medium in a half cycle of the fluctuation cycle of the carrying speed of the recording medium is the shortest length along a predetermined direction of the magnetic or optical change given to the recording medium. It is preferable that the recording medium is conveyed so that the information becomes larger than the predetermined value by a predetermined value or more.

According to a fourth aspect of the present invention, an information recording method is provided in which a recording medium is conveyed along a predetermined direction, and information is recorded by giving a magnetic or optical change to the recording medium based on a recording signal. The relationship between the recording density of the information for correctly recording the information represented by the recording signal on the recording medium and the average value of the conveyance speed of the recording medium and the fluctuation range of the conveyance speed is obtained in advance, and It is characterized in that the recording medium is conveyed and the information is recorded so that the information represented by the recording signal is correctly recorded on the recording medium based on the relationship.

Further, the distance for carrying the recording medium in a half cycle of the fluctuation cycle of the carrying speed of the recording medium is more than the shortest length along the predetermined direction of the magnetic or optical change given to the recording medium. It is preferable to convey the recording medium so that the recording medium is small or substantially equal to record information.

Further, the distance for carrying the recording medium in a half cycle of the fluctuation cycle of the carrying speed of the recording medium is shorter than the shortest length along the predetermined direction of the magnetic or optical change given to the recording medium. It is preferable that the recording medium is conveyed so that the information becomes larger than a predetermined value and the information is recorded.

[0019]

According to the first aspect of the present invention, the relationship between the average value of the conveyance speed of the recording medium and the fluctuation range of the conveyance speed for correctly reading the information for a predetermined recording density is obtained in advance. For example, when the sheet is conveyed at a constant conveying speed, as shown in FIG.
When the read signal as shown in (D) is obtained, if the conveyance is performed so that the magnitude relationship between the pulse intervals t ₁ and t ₂ of the read signal is not reversed due to the change in the conveyance speed, the reading error due to the change in the conveyance speed may occur. The information can be read correctly without occurrence of. Therefore, in the above case, as the relationship between the average value of the transport speed of the recording medium and the fluctuation range of the transport speed for correctly reading the information, the average value of the transport speed at which the pulse interval t ₁ becomes smaller than the pulse interval t ₂ And the fluctuation range can be obtained.

By the way, as shown in FIG. 11 mentioned above,
For example, when a photographic film is conveyed by a pulse motor or the like in a photographic processing apparatus or the like, the conveying speed fluctuates in a substantially constant cycle with respect to the target conveying speed, and the fluctuation range is also substantially constant. When the recording medium is conveyed by a pulse motor or the like, it is considered that the conveying speed fluctuates at a constant cycle almost similarly to FIG. 11, so that the recording medium is conveyed at a target conveying speed, that is, an average value of the conveying speeds. If the fluctuation range of the transport speed that fluctuates in a cycle is obtained, it can be approximated by a sine wave model.

Therefore, the above-mentioned relationship is calculated by applying the above-mentioned sine wave model or the like, and calculating a curve showing the relationship between the average value of the transport speed and the fluctuation width at which the pulse intervals t ₁ and t ₂ are equal as shown in FIG. It can be obtained by obtaining the range (corresponding to the OK zone shown in FIG. 1) in which t ₁ is t ₂ or less. In the above relationship, if the recording medium is conveyed and the information is read so that the average value and the fluctuation range of the conveyance speed fall within the above range, the reading error does not occur due to the fluctuation of the conveyance speed at the time of reading the information. The average value and the fluctuation range of the transport speed differ depending on the configuration of the transport system including a driving unit such as a motor for transporting the recording medium, and can be adjusted by changing the configuration of the transport system. The above relationship can also be experimentally obtained by carrying out reading at various carrying speeds and varying widths.

Further, the inventor of the present application has found that the recording medium on which information is recorded at a predetermined recording density so that the reading signal as shown in FIG. 12D can be obtained when the recording medium is conveyed at a constant conveying speed. As to the above, with the recording density as a parameter, assuming that the transport speed fluctuates at a constant cycle as described above, the relationship between the average value of the transport speeds at which the pulse intervals t ₁ and t ₂ are equal and the fluctuation width was obtained by simulation. (Fig. 2
reference).

In FIG. 2, the transport speed V is V = AS + SF × sin (2πft + tp) where AS: average speed SF: fluctuation range of speed fluctuation f: frequency of speed fluctuation (variation period T = 1 / f) tp : The phase is approximated and the frequency f is set to 150 Hz by experiment.
Further, since the ratio of the pulse intervals t ₁ and t ₂ changes depending on the phase tp, the phase tp is shifted over one cycle of fluctuation, and if there is a phase where the pulse intervals are equal, the average value of the transport speed at this time, The above-mentioned relationship is obtained by plotting points corresponding to the fluctuation range on the diagram of FIG.

As shown in FIG. 2, the curve showing the above-mentioned relationship is bent in the middle (hereinafter, this bending point is simply called a bending point), and the average value and the fluctuation range of the conveying speed at the bending point are Although it varies depending on the recording density, the inclination is positive and the inclination is large in the range where the average value of the conveying speed and the fluctuation range are smaller than the bending point at any recording density, and the inclination is the boundary at the bending point. When the value becomes negative or becomes very small, and the average value of the transport speed and the fluctuation range become large, the inclination turns into a positive and large inclination.

The inventor of the present application has found that the distance at which the recording medium is conveyed at this bending point is a half cycle of the fluctuation cycle of the conveying speed.
It has been found that it is equal to the shortest length along a predetermined direction of the magnetic or optical change given to the recording medium (for example, the shortest magnetization width in magnetic recording, and the minimum width of bar and space in optical recording). .

FIG. 3A for explaining a case where, for example, information is magnetically recorded in the range in which the average value of the transport speed is smaller than the bending point and the fluctuation range is included in the OK zone.
As shown in (B) and (B), the distance by which the recording medium 10 is conveyed in one cycle of fluctuations in the conveying speed is smaller than the shortest magnetization width L1 of the recording medium 10. Therefore, when the recording medium 10 is conveyed by the shortest magnetic width L1, the conveyance speed changes by one cycle or more (about 2 cycles in FIG. 3B), so that the distances L1 and L2 corresponding to the widths of the respective magnetized portions. The average transport speed when transported is close to the average value.

Therefore, in the above, the ratios t ₁ ': t ₂ ', t ₁ ": t ₂ " of the respective pulse intervals of the read signal 12 shown in FIG. 3C are close to the ratio L1: L2 of the magnetization width, Since at least the magnitude relationship between t ₁ 'and t ₂ ' and t ₁ "and t ₂ " of the read signal 12 is not reversed, the recording medium is conveyed at a half cycle of the fluctuation cycle of the recording medium conveying speed. When information is read by transporting the recording medium so that the distance is smaller than or substantially equal to the shortest length along the predetermined direction of the magnetic or optical change given to the recording medium, It is possible to prevent a reading error from occurring due to a change in the transport speed of the sheet.

Further, the average value of the transport speeds rather than the bending point
Is larger than a predetermined value and the fluctuation range is included in the OK zone.
As shown in FIGS. 3 (A) and 3 (D),
In addition, the recording medium 10 is conveyed in one cycle of fluctuation of the conveying speed.
The distance is larger than the shortest magnetization width L1 by a predetermined value or more. This
Therefore, a predetermined number is required during one cycle of transportation speed fluctuation.
Since each pulse is detected, the
The fluctuation of the feeding speed is relatively small, and at least Fig. 3 (E)
The pulse interval t of the read signal 12 shown₁'And t₂', T ₁"And t₂"
The magnitude relationship between the two will not be reversed. Therefore, the recording medium
The recording medium is transported in a half cycle of the fluctuation cycle of the transport speed of
The distance is magnetic or optical given to the recording medium.
More than a predetermined value than the shortest length along a predetermined direction
You can read the information by transporting the recording medium so that it becomes larger.
For example, if there is a reading error due to fluctuations in the transport speed when reading information,
Occurrence is prevented.

According to a fourth aspect of the present invention, the relationship between the recording density of information for correctly recording the information represented by the recording signal on the recording medium, the average value of the conveying speed of the recording medium, and the fluctuation range of the conveying speed is shown. Ask in advance. As an example, when a recording medium is conveyed and the recording signal as shown in FIG. 12B is supplied to the recording head to record information, the magnetization width T ₁ shown in FIG. If the paper is conveyed so that the magnitude relationship of T ₂ is not reversed, the information can be correctly read by carrying the paper at a constant speed when reading the information. By the way, the relationship between the average value of the transport speed and the fluctuation range for correctly recording information changes depending on the information recording density, as shown in FIG. When recording information, the recording density is arbitrary as compared with the case where information already recorded at a predetermined recording density on the recording medium is read. Therefore, in the above case, the magnetization width T ₁ is changed to the magnetization width T _{2 in} consideration of the information recording density.
It suffices to find the relationship between the recording density of smaller information, the average value of the transport speed, and the fluctuation range.

Therefore, the above relationship is calculated by applying a sine wave model or the like and calculating a curve (see FIG. 4) showing the relationship between the average value and the fluctuation width of the transport speed at which the magnetization widths L1 and L2 are equal with the recording density as a parameter. This can be obtained by obtaining the range (OK zone in FIG. 4) in which L1 is L2 or less for each recording density. The principle of obtaining the average value and the fluctuation range of the transport speed for recording the information so that it can be read correctly is the same as the case of reading the information. Therefore, the above relationship becomes the same as in the case of reading information (FIG. 2), and if the recording medium is conveyed and the information is recorded so that the average value of the conveying speed and the fluctuation range are within the OK zone at the predetermined recording density. The reading error does not occur due to the fluctuation of the transport speed at the time of recording information.

The information recording density is determined by the transport distance with respect to the pulse intervals T ₁ and T ₂ of the recording signal. For this reason, when information is recorded at a predetermined recording density, the recording medium reaches a predetermined recording density after it is determined that the average value and the fluctuation range of the conveyance speed of the conveyance system fall within the OK zone of the predetermined recording density. As described above, the pulse intervals T ₁ and T ₂ of the recording signal may be adjusted. It is also possible to set a recording density such that it enters the OK zone with respect to the average value and fluctuation range of the transfer speed of the transfer system, and adjust the pulse intervals T ₁ and T ₂ so that the set recording density is achieved.

By the way, the curve shown in FIG. 4 is magnetically or optically given to the recording medium by the distance for conveying the recording medium in a half cycle of the fluctuation cycle of the conveying speed of the recording medium, like the curve in FIG. Bending at a point where the change becomes equal to the shortest length along a predetermined direction. 5 illustrates a case where information is magnetically recorded in a range in which the average value of the transport speed is smaller than the bending point and the fluctuation range is included in the OK zone.
As shown in (A) and (B), the distance for transporting the recording medium 10 in one cycle of variation of the transport speed is smaller than the shortest pulse width t ₁ of the recording signal 14. Therefore, when the recording medium 10 is conveyed at the pulse interval t ₁ hour, the conveyance speed is 1
Since it fluctuates by more than one cycle (about 1.5 cycles in FIG. 5B), as shown in FIG. 5C, the average when transported by distances L1 and L2 corresponding to the width of each magnetized portion of the recording medium 10 The transport speeds are close to the average value.

Therefore, in the above, the ratio of the magnetization widths L1 ': L
2 ′, L1 ″: L2 ″ is the ratio t ₁ : t of the pulse intervals of the recording signal
_It becomes close to ₂ , and at least the magnetization width L1 'and L2', L1 "and L
Since the magnitude relationship of 2 "is not reversed, the distance to carry the recording medium in a half cycle of the fluctuation cycle of the conveying speed of the recording medium is the predetermined direction of the magnetic or optical change given to the recording medium. If information is recorded by conveying the recording medium so that it is smaller than or substantially equal to the shortest length along
It is possible to prevent the occurrence of a reading error due to a change in the transport speed at the time of recording information.

In the range where the average value of the conveying speed is larger than the bending point by a predetermined value or more and the fluctuation range is included in the OK zone, the conveying speed is, for example, as shown in FIGS. 5 (A) and 5 (D). The distance that the recording medium 10 is conveyed in one cycle of fluctuation of is larger than the shortest pulse interval t ₁ of the recording signal 14 by a predetermined value or more. For this reason, the magnetization direction of the magnetization is reversed a predetermined number of times in correspondence with a predetermined number of pulses during the conveyance in one cycle of fluctuations in the conveyance speed, as shown in FIG. There is relatively little fluctuation in the transport speed of
At least the magnitude relationship between the magnetization widths L1 'and L2' and L1 "and L2" is not reversed. Therefore, the distance for carrying the recording medium in a half cycle of the fluctuation cycle of the carrying speed of the recording medium is more than a predetermined value than the shortest length along the predetermined direction of the magnetic or optical change given to the recording medium. When the recording medium is conveyed so as to be large and the information is recorded, the occurrence of a reading error due to the fluctuation of the conveying speed at the time of recording the information is prevented.

In the above description, the case of reading magnetically recorded information has been described as an example, but the same applies to the case of optically recording information. For example, in a state where the recording medium having photosensitivity is conveyed at a constant conveying speed, FIG.
The recording signal 16 shown in FIG.
When a light source or the like is caused to emit light in the section where 6 is at a high level and exposed, as shown in FIG.
The bars 18A having the width dimension corresponding to the high level time are recorded at a distance corresponding to the low level time of the recording signal 16.

When this recording material is conveyed and is read by, for example, detecting light transmitted through the recording medium, a read signal 20 as shown in FIG. 6C is obtained. If the transport speed changes during information reading, the high level and low level sections of the read signal 20 change. However, if the present invention is applied as described above, the relations shown in FIGS. 2 and 4 are obtained in advance, and the recording medium is conveyed so as to be included in the OK zone to record and read the information, the information It is possible to prevent a reading error.

[0037]

Embodiments of the present invention will now be described in detail with reference to the drawings. 7 and 8 show a negative film 30 according to this embodiment. The negative film 30 is provided with an emulsion layer 32 on the upper surface of the transparent base 31 in FIG. 8 so that an image is exposed and recorded. On the lower surface of the transparent base 31 shown in FIG.
The magnetic recording layer 33 is formed by coating the entire surface of the magnetic recording layer 33.
As shown in FIG. 7, the magnetic recording layer 33 has a recording track S1 along the longitudinal direction of the negative film 30 at the leading end of the negative film 30 where the image frame 30A is not recorded.
Information is recorded in S2, and in the portion where the image frame 30A is recorded, information is recorded in the recording tracks T1 and T2 corresponding to each image frame.

Information for each one of the negative films 30, for example, information for specifying the user of the negative film 30, is recorded on the recording tracks S1, S2, and information for each image frame 30A, for example, an image is recorded on the recording tracks T1, T2. Information indicating the shooting condition of the frame 30A and user information for each image frame are recorded. Further, at the tip positions of the recording tracks S1 and S2 and the tip positions of the recording tracks T1 and T2, one perforation 34 is provided for each image frame 30A. In addition, at the tip of the negative film 30,
A plurality of perforations 35 are provided for hooking and pulling out the negative film 30 on the claws of a sprocket (not shown).

FIG. 9 shows a camera 50 to which the present invention can be applied.
And a photographic processing system with a photographic printer 60. On one side of the camera 50, a cartridge 36 for accommodating the negative film 30 wound around a spool 52 is loaded. The camera 50 includes a drive reel 5 driven by a pulse motor 37 (see FIG. 10).
4 are provided. The end of the negative film 30 is hooked on the drive reel 54 and conveyed, and an image is taken. The negative film 30 for which a predetermined frame has been photographed is rewound onto the spool 52 of the cartridge 36. The pulse motor 37 is connected to the control circuit 38, and the control circuit 38
Operation is controlled by.

An optical system 40 including a lens 39 and a shutter (not shown) is connected to the control circuit, and the operation of the optical system 40 is controlled to record an image on the negative film 30. Further, in the control circuit 38, information indicating shooting conditions for each image frame 30A, such as the aspect ratio of the image frame 30A recorded on the negative film 30, exposure at the time of shooting, light source information, etc., is output from the optical system after the image frame 30A is shot. Is entered. Further, the camera 50 is provided with an operation unit 41. Information for identifying a user such as a user ID, name, address, etc., title, keyword, shooting location, etc. and user information for each image frame 30A such as title, keyword, shooting location, etc. are input from the operation unit 41 by manual operation. It

A magnetic head 56 is provided inside the camera 50 corresponding to each track of the negative film 30. The magnetic head 56 is connected to the control circuit 38 via the recording current amplifier 42 and the modulator 43. The control circuit 38 edits the information input from the optical system 36 and the operation unit 41 for each data to be recorded on each track, and outputs it to the modulator 43 when the negative film 30 is conveyed by the motor 30. The modulator 43 converts the input data into a write signal for magnetic recording. The write signal is amplified by the recording current amplifier 42 and supplied to the magnetic head 56, whereby the information is recorded on each track.

In the camera 50, after recording information on each track by the magnetic head 56, the magnetic head 56
The so-called verification is performed to read and confirm the above information. The read signal output from the magnetic head 56 by this verification is input to the control circuit 32 after being amplified by the amplifier 44. Negative film 30 after shooting
Is taken out from the camera 50 after being rewound into the cartridge 36, and brought into the lab. In the lab, the negative film 30 is developed, fixed, washed with a developing device (not shown),
After the drying process, the photo printing device 60 is set.

The photographic printing apparatus 60 is provided with a negative carrier 64 arranged on the optical axis of the light source 62. A drive roller (not shown) that is rotated by the drive force of the pulse motor 66 is attached to the negative carrier 64, and the negative film 30 is conveyed in the direction of arrow A in FIG. 9 by this drive roller. The pulse motor 66 is connected to the control circuit 78, and its operation is controlled by the control circuit 78.
Further, the negative carrier 64 is provided with a solenoid 68. The solenoid 68 can sandwich and press the negative film 30 at the printing position in accordance with an instruction from the control circuit 78.

C is provided between the light source 62 and the negative carrier 64.
Each MY filter 70 is interposed, and each filter is controlled by the control circuit 78 so as to appear and disappear on the optical axis according to the exposure amount of each color. The light rays that have passed through the negative film 30 are irradiated onto the photographic printing paper 74 via the lens 72, and the image of the image frame 30A is printed on the photographic printing paper 74. A shutter 76 is interposed between the photographic printing paper 74 and the lens 72, and is retracted from the optical axis at the time of exposure according to an instruction from the control circuit 78. Further, a reading head 80 is arranged on the upstream side of the negative carrier 64 on the conveyance path of the negative film 30. The reading head 80 is the camera 5
The magnetic head 56 of 0 can read the information magnetically recorded on each track. The output end of the read head 80 is connected to the amplifier 82, and a weak signal output from the read head 80 is amplified and output. Amplifier 82
The output terminal of is connected to the control circuit 78.

A recording head 92 for magnetically recording information on each track of the magnetic recording layer 33 is disposed downstream of the negative carrier 64. The control circuit 78 edits the data representing the exposure conditions and the like when the printing process is performed by the photo printing device 60, and outputs the edited data to the modulator 88. In the modulator 88,
The binary data “10 ...” Input from the control circuit 78 is converted into a write signal similarly to the modulator 43 and output to the write current amplifier 90. The recording current amplifier 90 amplifies the write signal and supplies it to the recording head 92.

As described above, information is temporarily magnetically recorded on each track of the negative film 30 by the magnetic head 56 of the camera 50, and this information is read and confirmed by the magnetic head 56, and at the same time, the information of the photographic printing apparatus 60 is read. It is read by the read head 80. Also, photo printing device 6
At 0, information is magnetically recorded by overwriting the information recorded on each track of the negative film 30 by the recording head 92, and this information is read by a reading head or the like of a photographic processor (not shown) in the downstream process.

In the camera 50, the motor or the like for feeding the negative film 30 is powered by a battery, and the feeding speed of the negative film 30 needs to be relatively low in consideration of the life of the battery. As shown in FIG. 4, when the transport speed is relatively low,
Specifically, when it is lower than the inflection point, the lower the information recording density, the wider the OK zone, and the less likely it is to be affected by fluctuations in the transport speed during information recording. Therefore, in this embodiment, the recording density of information in the camera 50 is as low as possible (for example, 50
bpi)), and the configuration of the transport system of the camera 50 including the pulse motor 37 is determined so that the average value of the transport speed and the fluctuation range are within the OK zone. With this,
The average value and fluctuation range of the transport speed when the information is read by the magnetic head 56 of the camera 50 are also within the OK zone shown in FIG. Therefore, the information reading error does not occur due to the fluctuation of the conveyance speed at the time of recording and reading the information in the camera 50.

In the photo printing apparatus 60, the negative film 30 is processed in order to process a large amount of the negative film 30 in a short time.
It is preferable that the conveyance speed of the is high. Therefore, in the photo printing apparatus 60, the conveying speed of the negative film 30 is set to be high, and more specifically, the conveying speed at the bending point of the recording density of the information recorded by the camera 50 is set to be a predetermined value or more, and the recording density is set to the above value. So that the average value and the fluctuation range of the transport speed of the transport system are within the OK zone (see FIG. 2) in
The configuration of the transport system of the photo printing apparatus 60 including the pulse motor 66 is defined. As a result, when the information is read by the read head 80 of the photo printing apparatus 60, a reading error does not occur due to a change in the transport speed.

In the region where the conveyance speed is higher than the bending point, the OK zone becomes narrower as the recording density becomes lower. However, the photographic processing apparatus including the photographic printing apparatus 60 has a conveyance system which is smaller than that of the camera 50. Since the precision is high, it is relatively easy to configure the transport system so that the average value and the fluctuation range of the transport speed of the transport system are within the OK zone even if the recording density is low.

On the other hand, the recording head 92 of the photographic printing apparatus 60
When information is recorded by, the information recording density is set as high as possible (for example, about 600 bpi). As described above, in the photo printing apparatus, the negative film 30 is conveyed at a high speed. When the transport speed is high, specifically, higher than the bending point by a predetermined value or more, the OK zone becomes wider as the information recording density becomes higher as shown in FIG. On the other hand, in the photo processor 60, the average value and the fluctuation range of the negative film 30 conveyance speed are set so as to be within the OK zone even when the recording density is low. Therefore, a reading error occurs due to the fluctuation of the conveyance speed during information recording. There is nothing to do.
Further, since the photographic printing apparatus 60 records information at a high recording density, in addition to the information recorded by the camera 50, it becomes possible to record the printing conditions and the like determined during the printing process on each track of the negative film 30. .

In this embodiment, the present invention is applied to the case of magnetically recording and reading information on the negative film 30. However, the present invention is not limited to this, and is optically It is also applicable when recording and reading information. The recording medium is various media such as a magnetic tape coated with a magnetic material when magnetically recording or reading information, and a photosensitive medium when optically recording or reading information. A medium such as a material can be applied.

[0052]

As described above, according to the first aspect of the invention, the relationship between the average value of the conveyance speed of the recording medium and the fluctuation range of the conveyance speed for correctly reading the information for the predetermined recording density is shown. Since it is obtained in advance and the information is read by transporting the recording medium so that the information can be correctly read based on the above relationship, it is possible to prevent the occurrence of a reading error due to the variation of the transport speed. The effect is obtained.

According to the fourth aspect of the present invention, the relationship between the recording density of the information for correctly recording the information represented by the recording signal on the recording medium, the average value of the conveying speed of the recording medium, and the fluctuation range of the conveying speed is shown. Since the information is recorded in advance by carrying the recording medium so that the information represented by the recording signal is correctly recorded on the recording medium based on the above relationship, a read error due to fluctuations in the carrying speed may occur. The excellent effect of being able to prevent the occurrence is obtained.

[Brief description of drawings]

FIG. 1 is a schematic diagram of a diagram showing a relationship between an average value of conveyance speeds and a fluctuation range in which pulse intervals t ₁ and t _{2 of} read signals are equal.

FIG. 2 is a diagram showing a result obtained by simulating a relationship between an average value of the transport speed and a fluctuation range, assuming that the transport speed at the time of reading fluctuates in a constant cycle with the recording density as a parameter.

FIG. 3A is a plan view showing a magnetized state of a recording medium, and FIG. 3B is a diagram showing a transport speed when a transport distance in a half cycle of a fluctuation cycle is smaller than a minimum magnetization width; (C) is a waveform diagram showing a read signal when the sheet is conveyed at the conveying speed shown in (B), and (D) shows the conveying speed when the conveying distance in the half cycle is larger than the minimum magnetization width by a predetermined value or more. Diagram,
(E) is a waveform diagram showing a read signal when the sheet is conveyed at the conveying speed shown in (D).

FIG. 4 is a diagram showing a result obtained by simulating a relationship between an average value of the conveyance speed and a fluctuation width, assuming that the conveyance speed at the time of recording changes in a constant cycle with the recording density as a parameter.

5A is a waveform diagram showing a recording signal, FIG. 5B is a diagram showing a transport speed when a transport distance in a half cycle of a fluctuation cycle is smaller than a minimum magnetization width, and FIG. FIG. 7A) is a plan view showing the magnetization state of the recording medium when it is carried at the carrying speed shown in FIG. , (E)
FIG. 6A is a plan view showing a magnetized state of a recording medium when it is conveyed at a conveyance speed shown in FIG.

6A is a waveform diagram showing a recording signal when optically recording information, FIG. 6B is a plan view showing a recording medium on which information is optically recorded, and FIG. 6C is a read signal. It is a waveform diagram showing.

FIG. 7 is a plan view of the negative film according to the present embodiment.

8 is a cross-sectional view taken along the line VIII-VIII of FIG.

FIG. 9 is a schematic configuration diagram of a photographic processing system.

FIG. 10 is a schematic configuration diagram around a control circuit of the camera.

FIG. 11 is a diagram showing an example of fluctuations in film transport speed when a photographic film is frame-fed and transported.

12A is a waveform diagram showing a signal created according to information, FIG. 12B is a recording signal of the signal shown in FIG. 12A, and FIG. FIG. 3D is a plan view showing the magnetization state of the magnetic recording portion, and FIG. 3D is a waveform diagram showing a read signal when the information is read while being conveyed at a constant speed.

13A is a waveform diagram showing a recording signal, FIG. 13B is a diagram showing a change in transport speed, and FIG. 13C is a diagram showing magnetization in a magnetic recording portion in a changing state as shown in FIG. 13B. FIG. 4D is a plan view showing the state of FIG. 3D, and FIG. 4D is a waveform diagram showing a read signal when the magnetic recording portion of FIG.

14A is a plan view showing a magnetized state of a magnetic recording portion, FIG. 14B is a diagram showing a change in transport speed, and FIG. 14C is a state in which the magnetic recording part is changed as shown in FIG. It is a wave form diagram which shows the read signal at the time.

[Explanation of symbols]

 10 Recording Medium 12 Reading Signal 14 Recording Signal 30 Negative Film 33 Magnetic Recording Layer 37 Pulse Motor 50 Camera 56 Magnetic Head 60 Photographic Printing Device 66 Pulse Motor 80 Reading Head 92 Recording Head

Claims (6)

[Claims] 1. A recording medium is conveyed along a predetermined direction,
An information reading method for reading the predetermined information by detecting a magnetic or optical change representing the predetermined information given to the recording medium at a predetermined recording density, wherein the information is read for the predetermined recording density. The relationship between the average value of the transport speed of the recording medium for correct reading and the fluctuation range of the transport speed is obtained in advance, and the recording medium is transported to read the information so that the information can be correctly read based on the relationship. An information reading method characterized by the above. 2. The shortest distance along which a recording medium is conveyed in a half cycle of the fluctuation period of the recording medium conveying speed is along a predetermined direction of a magnetic or optical change given to the recording medium. 2. The information reading method according to claim 1, wherein the recording medium is conveyed so that the information is read so as to be smaller than or substantially equal to the length. 3. The shortest distance along which the recording medium is conveyed in a half cycle of the fluctuation period of the conveying speed of the recording medium is along a predetermined direction of a magnetic or optical change given to the recording medium. 2. The information reading method according to claim 1, wherein the information is read by transporting the recording medium so as to be larger than the length by a predetermined value or more. 4. A recording medium is conveyed along a predetermined direction,
An information recording method for recording information by giving a magnetic or optical change to the recording medium based on a recording signal, the recording of information for correctly recording the information represented by the recording signal on the recording medium. The relationship between the density and the average value of the transport speed of the recording medium and the fluctuation range of the transport speed is obtained in advance, and the recording medium is recorded so that the information represented by the recording signal is correctly recorded on the recording medium based on the relationship. An information recording method, characterized in that the medium is conveyed to record information. 5. A distance for transporting the recording medium in a half cycle of a variation cycle of the transportation speed of the recording medium is defined as a minimum length along a predetermined direction of a magnetic or optical change given to the recording medium. 5. The information recording method according to claim 4, wherein the recording medium is conveyed such that the recording medium is small or substantially equal to the recording medium. 6. The distance for carrying the recording medium in a half cycle of the fluctuation cycle of the carrying speed of the recording medium is more than a shortest length along a predetermined direction of a magnetic or optical change given to the recording medium. 5. The information recording method according to claim 4, wherein the recording medium is conveyed so that the information becomes larger by a predetermined value or more.