JP2001351240A - Optical recorder, optical recording method and digital still camera - Google Patents

Abstract

PROBLEM TO BE SOLVED: To eliminate delays in write interval, with respect to recording medium due to the execution of the detecting operation of the optimum laser output value at writing, by saving the trial writing area. SOLUTION: This recorder is provided with an image pickup part 10, an image signal arithmetic processing part 11 for converting the image picked up to the image signal, a display part 12 for displaying the operation information, image signal, etc., an OP part 13 for writing and/or reading with respect to the recording medium, an RF processing part 14 for RF processing the read- out signal, a servo signal processing part 15 for producing the servo signal from the RF signal, an analog filter processing part 16 for generating an analog signal for controlling each driver, on the basis of the servo signal, a signal processing part 17 for processing the read-out signal, spindle driver 18, thread driver 19, tracking driver 20 for rocking the OP part 13, focus driver 21, spindle motor 22 for driving the recording medium, thread motor 23 for moving the OP part 13, temperature-detecting sensor 24, and control part 25, then the trial wiring is carried out according to the condition.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical recording apparatus, an optical recording method, and a digital still camera for recording data on a recording medium using a laser beam, and more particularly to a recording medium using a laser beam. An optical recording device that saves the area consumed by test writing with laser light when recording on
The present invention relates to an optical recording method and a digital still camera.

[0002]

2. Description of the Related Art A so-called CD to which optical reading is applied.
(Compact Disc).
Recorded as an optical disk. ) Has a large storage capacity and allows random access. In addition, since optical reading is non-contact, there is no danger such as head crash or wear and damage due to reading as compared with a contact type recording medium such as a magnetic tape. Also, because the disc surface is sturdy,
There is less danger of accidental data loss. An optical disc having many advantages as described above is an excellent recording medium as a memory around a computer and in data production and data storage.

In recent years, CD-Rs (Compact Disc-Rec
A recording / reproducing apparatus using a write-once optical disc called ordable) has been developed. Some of these CD-Rs can easily be written to all standard formats used on compact discs, such as CD-ROM, CD-ROM / XA, CD-I, and CD-DA. Some can. CD-Rs are mounted on electronic devices instead of conventional magnetic tapes, magnetic disks, etc., to record and / or record data.
Or, it is being used as a recording / reproducing device for reproducing.

A laser diode used in a CD-R has a laser output for writing that varies depending on characteristics of each recording medium and an ambient temperature. PCA (Power Calibration Are
By performing the test writing by gradually changing the laser output level in the test writing area called a), the optimum writing output is determined under the environment at that time. This operation is called Optimum PowerCalibration (OPC).

According to the CD-R standard, ATIP (Absolite Time In Per-groove, Modulati
In the predetermined format of ng), time information on the medium and information such as the start time of the lead-in area are coded and written at a rate of one frame per 10 frames.

[0006] This is also used as an identification code for individually identifying a maker and a recording medium, and the writing characteristics of each recording medium specified by the code described here are stored in the recording apparatus in advance. Have been. And the recording device,
Various parameter groups related to writing are obtained, and the optimum parameter group corresponding to the identification code is selected and used at the time of writing. This is called a write strategy, and specifies an optimum value of the laser output when the laser pulse is partially changed in the time axis / intensity direction according to the EFM pulse length.

[0007]

SUMMARY OF THE INVENTION
In a CD-R, a write test area of a PCA (Power Calibration Area) is prepared for only about 100 times as a standard. Specifically, consider a case where a file having a file size of 64 Kbytes is written on a CD-R recording medium having a diameter of 12 cm. Since a CD-R recording medium having a diameter of 12 cm has a writing capacity of about 650 Mbytes, about 10,000 or more files of 64 kbytes as described above can be written. However, the area required for test writing to ensure sufficient writing accuracy is 100 times as standard, and even if the minimum required write test is performed, there is only a test area equivalent to 1500 times. It is the current situation.

Therefore, when a CD-R having a very large recording capacity is adopted as a recording device of a digital still camera,
There is a problem that the write test area of the PCA is consumed with repeated recording, and recording cannot be performed if the write test area for recording is completely consumed, even though the recording area has room. ing.

In particular, when a CD-R is used as a recording device of a digital still camera, the OPC operation is performed by executing the OPC operation in view of the responsiveness of the recording operation peculiar to the digital still camera for recording a captured image. There is a problem that a photographing interval becomes long.

The present invention has been proposed in view of such a conventional situation, and it is possible to save a test writing area, and to perform a recording medium by performing an operation of detecting an optimum laser output value at the time of writing. It is an object of the present invention to provide an optical recording apparatus and a method capable of eliminating a delay in a writing interval for writing data.

[0011]

In order to achieve the above object, an optical recording apparatus according to the present invention is an optical recording apparatus for recording data on a recording medium by optical recording. It has a writing means for writing data on the other hand and a control means for controlling whether or not to execute test writing when writing data to a recording medium.

Here, the control means may execute test writing in accordance with a change of a recording medium, a predetermined number of times, and a change in temperature.

In order to achieve the above-mentioned object, an optical recording method according to the present invention is an optical recording method for recording data on a recording medium by optical recording, wherein the data is written on the recording medium. In this case, it is characterized in that whether or not to execute test writing is controlled.

Here, when data is written, test writing may be performed in accordance with exchange of a recording medium, a predetermined number of times, and a change in temperature.

In order to achieve the above-mentioned object, a digital still camera according to the present invention comprises: an image pickup means for picking up an object; an image processing means for processing the picked-up image data; Recording and / or reproducing means for performing recording and / or reproduction, and when writing data to a recording medium,
Control means for controlling the presence / absence of test writing.

Here, the control means may execute test writing in accordance with a change of a recording medium, a predetermined number of times, and a change in temperature.

[0017]

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

A digital still camera shown as one configuration example of an embodiment of the present invention is a UDF (Universal Disk Format).
Based on a file system conforming to t), writing of captured image data and reading of image data from the recording medium are performed on a write-once recording medium, and the image data is stored. The test writing performed immediately before writing the file is executed according to the conditions.

UDF (Universal Disk Format) is a CD-R
(Compact Disc-Recordable), WORM (Write-Once Read)
-Many optical disk), CD-R / RW (Compact Disc-Record)
able / Rewritable), MO (Magnet Optical Disk), DVD
(Digital Versatile Disk) is one of the definitions for describing the character codes of file names and file attributes that can be used mutually for various media such as OSTA (Optica).
l Storage Technology Association).

In other words, the UDF is a file system that can be written from any OS, and the written file can be reproduced on any OS without a special reader program.

In the UDF, the main data structure is a file entry ICB (File Entry Information Control Bloc).
k) is used. In UDF, every file and directory has its own ICB. In the embodiment of the present invention, a file storing actual data such as image data of a captured image is generally written before an ICB that defines the file. When placed on the (data stream), the ICB can include a list of those extents.

In UDF, VAT (Virtual Allocation Tabl)
Using a mapping table called e), a sequential number (virtual address) for a virtual reference is assigned to each file. Whereas a file system conforming to the international standard ISO9660 refers to each file or directory on a recording medium directly by a logical address, UDF
Is referred by the virtual address as described above. VAT
Can be placed anywhere in the truck,
Further, the VAT is referred to by a VAT ICB indicating the location of the VAT.

In the UDF, it is determined that the VAT ICB is located at the last physical address recorded on the recording medium. The VAT is divided and arranged on a plurality of extents, but the VAT ICB includes a VAT extent list. Thus, in a UDF, if a file is modified in any way, the entire set of file pointers does not need to be changed, and eventually only the VAT ICB can be reached to the changed file .

In a UDF-compliant file system, the structure of a unit (hereinafter, referred to as a volume) for managing a detachable recording medium that accommodates files and the like is as shown in FIG.

In a UDF-compliant file system, a BEAD (Beginning) in an extended area recorded after 16 sectors when the beginning of a session is set to 0 sector.
Extended Area Descriptor) and TEAD (Terminating E)
VSD (Volume S) sandwiched between xtended Area Descriptor
tructure Descriptor) contains information for recognizing the UDF file system.

In a file system conforming to the UDF, in a state where data is written to a recording medium and before closing a session, an AVDP (Anchor Volume) in which an optical head reads first to reach a file is used to reach a file.
Descriptor Pointer). AVDP has a logical block number (LBN) of 512 when the beginning of a session is 0 sector.
It is described in the area of the sector.

That is, if the AVDP exists in the sector 512, it is understood that the AVDP is recorded based on the UDF-compliant file system. AVDP is composed of LBN = 256 sectors and LBN =
(LBN of last write sector) Described in two sectors of -256 sectors. After the closed session operation, the AVDP described in the sector 512 is not used for reading. AVDP stands for Volume Descriptor (hereinafter VDS: Volume Descriptor).
Described as scriptor Sequence. ). V
The DS group is described from sector 512 onward.

The VDS is a descriptor indicating information on the contents of the volume structure. The VDS has a basic volume descriptor and a logical volume descriptor (hereinafter referred to as LVD: Logical Volume Descriptor).
Write as ume Discription. ), Volume information such as an application volume descriptor, a virtual partition descriptor, and a real partition descriptor, and partition information.

There are two partitions, a real partition and a virtual partition. The real partition contains the actual logical address of the data recorded on the recording medium. On the other hand, the virtual partition is a table based on the virtual address of the data, and is a division of the area when the entire recording area of the recording medium is remapped from the physical address to the virtual address. The virtual partition is determined by VAT.

Further, two descriptors indicating a real partition and a virtual partition are placed in the VDS.
If the partition number is 0, the file system refers to the real partition, that is, the actual logical address, and if it is 1, the file system refers to the virtual partition (VAT).

The LVD in the VDS indicates a set of file set descriptors (hereinafter, referred to as FSDS: File Set Descriptor Sequence), that is, a set of file sets existing in the volume. Each FSDS is RDICB
(Root Directory Information Control Block), and the RDICB contains information such as specific directory names and file names.

A UDF-compliant file system suitable for packet writing has two unique data structures. File Entry ICB (File Entry ICB) for identifying each file existing in the file system
And a file identifier (FID)
Descriptor. ). The FID indicates the physical address of the file entry ICB. Or, via VAT,
Indirectly points to the file entry ICB.

The directory referred to by the RDICB is configured as a table in which related FIDs are collected. The file entry ICB contains all extent lists, dates, file attributes, and the like of the stored file. Therefore, the content of this file entry ICB is a physical address that may change when the file is changed or edited.

The FID points to the file entry ICB, and the file entry referenced by the file entry ICB points to an actual file. Since a directory is a type of file, a file entry can also point to a directory. Thus, the file system conforming to the UDF has a tree-like hierarchical structure.

As described above, the root directory can be referred to by RDICB. In the root directory, the FID for referring to the file entry ICB
Or contains an FID pointing to the directory entry ICB.

The FID has information such as "partition 1 / block 200". If the partition is 1, since it is a virtual partition, the file system directly accesses the logical address to search for a file.
Do not go to 200. Instead, it will first reference the VAT and point to the logical address via the VAT.

As a result of the above file system, the UDF executes an operation schematically shown in FIG. 2 in order to seek a file.

The optical head first reads the last area of the recorded area of the disk. Here is VAT ICB
Is described. VAT is read from VAT ICB.

Subsequently, the optical head refers to the AVDP in sector 256. Next, VDS described in AVDP is referred to.

From the VDS, it is determined whether the partition is a real partition or a virtual partition.

Further, the FSDS is referred from the VDS. The FSDS indicates the RDICB, and the RDICB indicates the root directory. The root directory contains an FID indicating the ID of each file.

Finally, if the partition flag of the VDS of the root directory constituted by the FID is a real partition, the physical address of the file entry ICB is directly referred to. If the flag is a virtual partition, File entry ICB via VAT
To the desired file.

By providing a VAT between the FID and the file entry ICB, even if the file entry ICB is rewritten, the file entry ICB is replaced on the VAT to virtually replace the file entry ICB address.
It can be treated as if the ICB was rewritten.

Therefore, even if the location of the file entry ICB is changed by, for example, changing the contents of the root directory, it is not necessary to rewrite the FID by changing the VAT.

In a file system conforming to the UDF, by performing the above-described seek operation, it is possible to treat a sequential write recording medium as if it were a random read / write recording medium.

Next, a specific configuration of the digital still camera shown as one configuration example of the embodiment of the present invention will be described with reference to FIG. The digital still camera, for example, writes and reads data to and from a recording medium. Here, as a write-once recording medium, a so-called CD-R (Compact Diode) having a disk shape is used.
sc-Recordable).

The digital still camera 1 includes an image pickup section 10 for picking up an image of a subject and an image signal processing section (Image Signal Processor) 1 for converting an image signal from the image pickup section 10.
1, a display unit 12 for displaying operation information for operating the digital still camera 1, an image signal, and the like, and an OP (Opti) for writing and / or reading from a recording medium described later.
cal Pickup) section 13, an RF processing section 14 for performing RF processing on a read signal, a servo signal processing section 15 for generating a servo signal from each signal from the RF processing section 14, and a servo signal processing section 1.
An analog filter processing unit 16 that generates an analog signal for controlling each driver based on the signal from the control unit 5;
A signal processing unit 17 for processing a read signal from a recording medium, which will be described later; a spindle driver 18 for controlling the rotation of a spindle motor; a thread driver 19 for controlling the operation of a thread motor; A tracking driver 20 for controlling the focus of the beam by moving the objective lens of the OP unit 13 in the vertical direction with respect to the disc-shaped recording medium;
Spindle motor 22 for driving a disk-shaped recording medium
A thread motor 23 for moving the OP unit 13 in the radial direction of the recording medium, a temperature detection sensor 24 for detecting a temperature around the OP unit 13, and a control unit 25 for controlling each unit. Then, writing of the captured image data and reading of the image data are performed.

The imaging unit 10 includes a lens unit 30 for capturing an image of a subject, and a charge-coupled device (hereinafter, referred to as a charge-coupled device) for generating image signals.
Notated as CCD. ) 31, a sampling / hold (hereinafter, referred to as S / H) circuit 32, and an A / D conversion circuit 33 for converting an image signal into a digital signal. CCD31
Generates an image signal from the subject image from the lens unit 30 and supplies the generated image signal to the S / H circuit 32. S / H
The circuit 32 samples and holds the image signal from the CCD 31, and then supplies the image signal to the A / D conversion circuit 33. A / D
The conversion circuit 33 converts the image signal from the S / H circuit 32 into a digital signal and supplies the digital signal to the image signal operation processing unit 11.

The image signal arithmetic processing unit 11 is controlled by the CPU to convert the digital image signal from the imaging unit 10 into RG
It performs image processing such as color standard form conversion from B signal to color difference / luminance signal, white balance processing, γ correction, reduced image processing, JPEG compression processing and the like. The processed image signal is stored in an SR
After temporarily stored in the AM, it is supplied to the signal processing unit 17.
Further, the image signal arithmetic processing unit 11 supplies the processed image signal to the display unit 12.

The display section 12 is, for example, a liquid crystal display (LCD), and displays an image signal from the image signal processing / calculating section.

The OP (Optical Pickup) section 13 includes an objective lens, a laser diode (LD), a laser diode driver (LDdrv), a photodetect IC (Photo Detect I).
C), including a half mirror, etc., detects an optical signal and outputs it to the RF processing unit 14. Further, when recording on the recording medium 26, a laser blinking / driving signal (DECEFMW) from the signal processing unit 17 necessary for pit formation, a signal (write strategy) indicating an optimum value of laser intensity and blinking, etc. The data is written to the recording medium 26 based on.

The RF processing unit 14 samples and holds the eight signals consisting of the beam signal, the side signal, and the main signal detected from the OP unit 13, performs an arithmetic operation,
FE (focus error), TE (tracking error), MIRR (mirror),
It generates signals such as ATIP (Absolute Time In Pregroove) and a read main signal. The RF processing unit 14 outputs the FMDT (Frequency Modulation Data), FMCK (Freque
ncy Modulation Clock), TE, FE, servo signal processing unit 1
5 and outputs an optimal value (OPC: Optical Power Calibration) signal of laser intensity blinking and laser blinking / driving signal detected by test writing to the signal processing unit 17 and outputs MIRR to the control unit 25. I do.

The servo signal processing unit 15 receives the FMDT (Frequency Modulation Data), FMCK (Frequency
ency Modulation Clock), TE, FE, and control unit 2
5 to generate signals for controlling various servos peculiar to the optical disc, and output them to the analog filter processing unit 16.

The analog filter processing section 16 generates analog signals from various servo control signals from the servo signal processing section 15 and outputs the analog signals to the spindle driver 18, thread driver 19, tracking driver 20, and focus driver 21.

The signal processing unit 17 is controlled by the control unit 25 and receives the OPC and DECFFM from the RF processing unit 14 to perform processing such as CIRC decoding and encoding, write strategy, ADdr decoding, asymmetry calculation, and running OPC. Do. When writing data to the recording medium, a signal such as a laser blinking / driving signal and a signal indicating an optimum value of the laser intensity is output to the OP unit 13.

The spindle driver 18 controls the rotation of the spindle motor 22 based on a signal from the analog filter processing section 16.

The thread driver 19 is controlled by a thread motor 23 based on a signal from the analog filter processing unit 16.
Control the thread behavior of

The tracking driver 20 oscillates the OP unit 13 based on a signal from the analog filter processing unit 16 to control the position of a beam spot irradiated on the disk surface of the recording medium 26.

The focus driver 21 controls the focus adjustment of the laser by moving the OP unit 13 in a direction perpendicular to the disk surface of the recording medium 26 based on the signal from the analog filter processing unit 16.

The spindle motor 22 rotates the recording medium based on a signal from the spindle driver 18.

The thread motor 23 performs a thread operation of the OP unit 13 based on a signal from the thread driver 19.

The temperature detection sensor 24 is installed near the OP unit 13, detects the temperature near the recording medium 26, converts the temperature into a signal indicating the temperature, and supplies the signal to the control unit 25.

The control unit 25 includes a program memory for storing programs for performing various processes, and an SRAM as a work area for temporarily storing the VAT ICB and various data.
(Static Random Access Memory) and a CPU, and controls whether or not to execute test writing according to conditions.
The control unit 25 inputs a signal indicating the temperature from the temperature detection sensor 24, and issues an instruction to execute test writing when the temperature change exceeds a predetermined amount. Further, the control unit 25 issues an instruction to execute test writing every time data is written a predetermined number of times. The control unit 25 controls each unit.

Here, the SRAM is specifically used as a work area for temporarily expanding the VAT ICB extracted from the recording medium. In the program memory, correction parameters for correcting the laser pulse at the time of writing in the time direction and the level direction for each pit so that the pit size after writing satisfies the standard when writing data are set. It is prepared.

The recording medium 26 is a write-once recording medium for writing and reading data based on a UDF-compliant file system, and has a so-called disk shape.
CD-R (Compact Disc-Recordable).

FIGS. 4 and 5 are cross-sectional views of the recording medium 26. FIG. FIG. 4 shows a cut surface when the recording medium 26 is cut perpendicular to the disk surface. FIG. 5 is an enlarged view of the inner peripheral side of the disk in the sectional view of FIG.

As shown in FIG. 4, the recording medium 26 has a power calibration area (PC).
A) and the program management area (Program Manegem)
entArea: PMA) and Lead-in Area
And an information area (Imformation Area).

As shown in an enlarged view of FIG. 5, the power calibration area includes a test area as an area for actually performing test writing, and a count area for counting the start position and the number of times of test writing. And

The areas indicated by oblique lines in FIGS. 4 and 5 indicate that recording has been completed.

The test area is divided into 100 partitions, and this partition is specified by a relative time from the start time of the lead-in area. Each partition consists of a minimum of one frame.
It is divided into sub-partitions, and one sub-partition is further divided into three frames. The laser output is adjusted by performing test writing immediately before writing using this subpartition.

In the digital still camera 1 configured as described above, the operation of each component when reading the signal recorded on the recording medium 26 will be described.

The light of the laser diode reflected from the disk surface of the recording medium 26 is read by the lens optical system of the OP unit 13. Light from the lens optics is converted to PDIC (Photo De
tectIC), is converted into an electric signal, is sampled and held in the RF processing unit 14, and focus error (FE), tracking error (TE), mirror (MIRR), ATIP (Absolute Time In P
regroove), a signal such as a read main signal is generated by arithmetic processing.

First, the focus error obtained by the RF processing unit 14 is determined by the servo signal processing unit 15 (Digital Servo
After the characteristic is adjusted by the processor, the signal is input to the focus driver 21 through the analog filter processing unit 16 (Analog Filter Block). Focus driver 2
1 moves the lens drive focus coil (not shown) of the OP unit 13 in the vertical direction to correct the focus shift.

Similarly, the tracking error obtained by the RF processing unit 14 is determined by the servo signal processing unit 15 (Digital Serv.
o Processor) to extract the AC component and apply digital filter processing. Thereafter, the signal passes through the analog filter processing unit 16 and is input to the tracking driver 20.
The tracking driver 20 finely moves the lens drive tracking coil of the OP unit 13 in the radial direction to correct the tracking deviation.

The tracking error obtained by the RF processing unit 14 is subjected to DC component extraction by the servo signal processing unit 15 and subjected to digital filter processing. After that, the thread driver 1 passes through the analog filter processing unit 16.
9 is input. The thread driver 19 operates the thread motor, moves the entire OP unit 13 in the radial direction of the recording medium, and corrects the deviation of the thread operation. During the seek operation, the sled motor is forcibly driven by intentionally applying the sled control voltage from the outside.

As described above, the tracking operation in which only the lens is finely moved in the radial direction based on the AC component of the tracking error is performed, and the sled operation for moving the entire OP unit 13 in the radial direction based on the DC component is performed. Will be

Since the detection signal (mirror) of the change in the reflectance of the recording medium output from the RF processing unit 14 is detected when the OP unit 13 crosses the track, the CPU counts the number of mirrors. It detects the current seek position and reading position, and starts and stops the optical pickup operation.

The control of the spindle motor 22 is performed by the ATIP (Ab
solute Time In Pregroove) processing.
In a meandering groove called a wobble groove written on a recording medium, time information is recorded by FM modulation of +/- 1 KHz at a center frequency of 22.05 KHz in a radial direction. Modulated is a bi-phase modulated ATIP (Ab
solute Time In Pregroove).

When the focus and tracking are matched, the RF processing unit 14 extracts a wobble signal from a predetermined combination of the eight input signals. FM demodulation, AT
It is subjected to IP decoding, and extracted as a clock signal (FMCK) corresponding to the center frequency and time information (FMDT).

The FMDT includes a servo signal processing unit 15 (Servo Pr.
ocessor), which is stored in a predetermined register classified as an absolute time position of the medium, that is, an address and other additional information. In response, the CPU reads via the BUS.

In a read operation, a signal corresponding to a recording pit is extracted from a predetermined combination of eight signals by the RF processing unit 14, and is subjected to equalizer processing.
Fourteen Moduration) Signal processing unit 1 in signal format
7 is supplied. In the signal processing unit 17, CIRC (Cross Inte
(rleave Reed-Solomon Code) to perform decoding to obtain desired data.

Next, the write operation will be described. In the writing operation, first, the pickup is moved to the lead-in area to read the ATIP information. In addition, Special Information 2 (Special Imformation
Read out part 2).

FIG. 6 shows an outline of the frame structure of ATIP written in the lead-in area. The special information 1 is described in the frame of the frame number N in FIG. 6, and the special information 2 is described in the frame number (N + 10). Also, the frame number (N +
Normal time codes are described in frames 1) to (N + 9) and (N + 11) to (N + 19).

In the special information area described every 10 frames, the start position of the lead-in area of the recording medium is written as time information. In the special information 2 area described in the frame number (N + 10) read out here, the start position of the lead-in area is also described as time information in a predetermined format.

For example, half a minute from the recording start point of the recording medium
If the lead-in area starts from the position where one second has elapsed, the special information 2 area of the recording medium 25 contains 100 minutes to 2 minutes 11 of the total recording time.
A signal obtained by digitizing time information of 97 minutes and 49 seconds obtained by subtracting seconds is described. That is, the time information “97:49:00” is described as “1001 0111 0100 1001 0000 0000”.

The information written in the special information area corresponds to an identification code for identifying a recording medium. In the recording medium reproducing apparatus, a write strategy parameter corresponding to the identification code and other related parameters are stored in advance as a table. The write strategy is a correction parameter for correcting the laser pulse at the time of writing for each pit in the time direction and the level direction so that the pit size after writing satisfies the standard. The playback device is provided with a write strategy for each recording medium in advance. The recording signal according to the write strategy is set in detail, for example, as shown in FIG.

FIG. 7A shows an EFM signal. FIG. 7 (b) shows the actual R when writing the EFM signal of FIG. 7 (a).
The F signal is shown. Here, the recording signal according to the write strategy starts writing with a delay of aT, and the initial (bT) period of writing is described with an output that is ΔP larger than Pw, and thereafter, is determined to be described with the output Pw. Have been.

Next, an OPC (Optimum Power Calibration) operation for determining the optimum value of the laser output is performed. While the above-described write strategy is the detailed control of the laser for each write pit, the OPC operation is an operation for calculating the optimum value of the laser output throughout the entire write operation. By performing OPC, it is possible to obtain a pit write set value for realizing an ideal read target value.

The OPC is performed in a test area of the PCA. The test area is divided into 100 partitions, and this partition is specified by a relative time from the start time of the lead-in area. Each partition is
It is further divided into a maximum of 15 frames. This one
The laser output is adjusted by performing test writing immediately before writing using the partition.

Specifically, the laser output is changed stepwise from a predetermined value, and writing is performed on the recording medium at each step.
The laser output at this time is read out, the asymmetry in each stage is measured, and the set value of the laser output indicating the target asymmetry value is obtained by linear approximation from the set value near the target asymmetry.

Here, the asymmetry value is 3TPit / Land
And the center level of 11TPit / Land is defined, and is a value calculated by the following equation (1). FIG. 8 shows the demodulation levels of the pits used in calculating the asymmetry value.

Asymmetry value (%) = (3T center−11T center) / 11T amplitude (1) The target asymmetry value is an ideal value that minimizes the jitter value, and this asymmetry value is Included in the write strategy parameter as a value specific to the recording medium,
It is stored in advance corresponding to the start position information of the lead-in area of the recording medium. Here, the target asymmetry value is -5
%.

FIG. 9 shows the relationship between the laser output during writing and the asymmetry value after writing. As can be seen from FIG.
The laser output during writing and the asymmetry value after writing are in a proportional relationship. The laser diode used for the optical pickup of the CD-R generally has a large fluctuation in the laser output with respect to the operating environment temperature, and even if the laser output is set to a target asymmetry value at room temperature, as shown in FIG. The laser output greatly changes according to the environmental temperature. As a result, as can be seen from the graph showing the relationship between the asymmetry value and the recording jitter value shown in FIG. 10, the fluctuation of the asymmetry value greatly affects the deterioration of the recording jitter value.

Therefore, the OPC operation for determining the optimum value of the laser output needs to be performed immediately before the writing operation. After the optimum setting of the laser output is performed by the above operation, the OPC operation is prepared as a fixed value. Optimum writing is realized by setting each parameter. The measurement of the asymmetry value is taken in from the A / D converter and is performed in the signal processing unit.

In the count area of the PCA, when at least one sub-partition in each partition is used by OPC, the corresponding partition in the count area is painted out. Next time, when performing the OPC, the OPC operation is performed after seeking an unused subpartition in the used partition of the PCA.

Specifically, at the time of writing, the compressed photographed image data prepared in the SRAM is subjected to CIRC or EFM encoding processing in a signal processor, and then a laser blinking / driving signal required for pit formation is formed. (DECEFMW),
The signal (write strategy) indicating the optimum value of the laser intensity is input to the laser driver of the OP unit.

At this time, the FMDT obtained by decoding the ATIP
Writing is performed at a predetermined position in timing along a file system based on an address in a frame unit obtained from a signal.

In the first writing, writing is started from a position where an area of about 20 Mbytes, which is a lead-in area, is skipped in a subsequent close session.

Next, a description will be given of a test writing operation process performed when the digital still camera 1 writes data to a recording medium.

In the embodiment of the present invention, when recording data, test writing is not necessarily performed every time.
It allows data to be recorded without trial writing. That is, when recording data, it is determined whether or not to execute the test writing according to a predetermined condition.

As a specific example of the condition for performing the test writing, when data is written to the recording medium for the first time, immediately after the recording medium is mounted or replaced, the number of times of data writing is counted and assigned to a predetermined number once. A case where data is written after a certain period of time has elapsed since the last test writing, a case where the environmental temperature of the recording medium or the apparatus has changed by a certain temperature difference or more, and the like.

Except for the above conditions, the execution condition of the test writing hardly changes, and appropriate data writing can be performed. Therefore, it is determined not to execute the test writing.

Hereinafter, a specific example of the present embodiment will be described with reference to FIG. In the following processing, after the test writing operation performed immediately before writing certain data, it is checked whether or not the recording medium has been replaced when writing the next data, and the test is performed when the recording medium has been replaced. A case where a process of executing a write operation and a process of performing test writing when the environmental temperature around the OP unit 13 has changed by a predetermined amount when writing the next data are performed in a series of processes. Have been.

In step S1, the control section 25 moves the pickup into the lead-in area and reads out the ATIP information.

In step S2, the control unit 25 sets the PM
Read A and check the free space on the recording medium.

In step S3, the start time of the lead-in area is read from the special information 2 area.

In step S4, the parameters of the write strategy corresponding to the start time are read from the SRAM, and the parameters of the write strategy are set.

In step S5, it is determined whether or not the recording medium has been replaced since the previous OPC operation. If the recording medium has been replaced, the process proceeds to step S8.

On the other hand, if the recording medium has not been replaced, the temperature around the OP section 13 is measured by the temperature detection sensor in step S6.

In step S7, it is determined whether or not the temperature difference from the previous OPC operation has reached a predetermined amount. If the temperature difference has not reached the predetermined amount, the process proceeds to step S9 to start writing data.

On the other hand, if the temperature difference has reached a predetermined amount,
Proceeding to step S8, in step S8, the control unit 24 executes test writing in a test area of the power calibration area.

Subsequently, in step S9, data writing is started.

Therefore, the digital still camera 1 shown as one configuration example of the embodiment of the present invention executes test writing in accordance with the exchange of the recording medium, the predetermined number of times, and the temperature change. , It is possible to save the test area consumption of PCA.

Also, since test writing is performed according to conditions,
OPC operation can be minimized. for that reason,
The delay of the writing interval to the recording medium is eliminated, and the operation of performing the next imaging and recording is performed smoothly.

Although the digital still camera 1 according to the embodiment of the present invention shows a case where writing is performed at 1 × speed, a digital still camera equipped with a recording device capable of writing at a speed higher than 2 × speed is shown. The same processing can be applied to a camera by converting various set values and standard values into values corresponding to the writing speed.

Further, the present invention is not limited to only the above-described embodiment, and it goes without saying that various modifications can be made without departing from the spirit of the present invention.

[0117]

As described in detail above, the optical recording apparatus according to the present invention is an optical recording apparatus for recording data on a recording medium by optical recording, and writes data on the recording medium. It has writing means and control means for controlling whether or not to execute test writing when writing data to a recording medium.

Here, the control means may execute test writing in accordance with a change of the recording medium, a predetermined number of times, and a temperature change.

Therefore, according to the optical recording apparatus of the present invention, test writing is performed in accordance with conditions, so that it is possible to reduce the consumption of the writing test area in repeated recording.

Also, since test writing is performed according to conditions,
It is possible to eliminate the delay of the writing interval to the recording medium and provide a recording operation with good responsiveness.

Further, the optical recording method according to the present invention is an optical recording method for recording data on a recording medium by optical recording. Control whether or not.

Here, when writing data, test writing may be performed in accordance with exchange of a recording medium, a predetermined number of times, and a change in temperature.

Therefore, according to the optical recording method of the present invention, test writing is performed in accordance with conditions, so that it is possible to reduce the consumption of the write test area in repeated recording.

Further, since test writing is performed according to conditions,
It is possible to eliminate the delay of the writing interval to the recording medium and provide a recording operation with good responsiveness.

Further, the digital still camera according to the present invention has an image pickup means for picking up an image of an object, an image processing means for processing the picked-up image data, and a recording / reproducing means for recording and / or reproducing data on a recording medium. Means for controlling the presence or absence of test writing when writing data to a recording medium.

Here, the control means may execute test writing in accordance with exchange of the recording medium, a predetermined number of times, and a change in temperature.

Therefore, according to the digital still camera of the present invention, test writing is performed in accordance with conditions, so that it is possible to reduce the consumption of the writing test area in repeated recording.

Also, since test writing is performed according to conditions,
It is possible to eliminate the delay of the writing interval to the recording medium and provide a recording operation with good responsiveness.

[Brief description of the drawings]

FIG. 1 is a diagram showing a management unit (hereinafter, referred to as a volume) structure of a removable recording medium that accommodates files and the like in a UDF-compliant file system.

FIG. 2 is a diagram schematically illustrating a file seek process in a UDF-compliant file system.

FIG. 3 is a block diagram showing a configuration of a digital still camera shown as an embodiment of the present invention.

FIG. 4 is a cross-sectional view showing a cut surface when a recording medium used in the digital still camera shown as an embodiment of the present invention is cut perpendicular to a medium surface.

FIG. 5 is a cross-sectional view showing a cut surface when a recording medium used in the digital still camera shown as an embodiment of the present invention is cut perpendicular to a medium surface.

FIG. 6 is a schematic diagram showing an outline of a frame structure of ATIP information written in a lead-in area of a recording medium used in the digital still camera shown as an embodiment of the present invention.

7A is a diagram showing the intensity of an EFM signal that changes with time, and FIG. 7B is a diagram showing the EF of FIG. 7A.
FIG. 3 is a diagram illustrating the actual RF signal strength when an M signal is written.

FIG. 8 is a diagram illustrating a pit demodulation level used when the digital still camera shown as the embodiment of the present invention calculates an asymmetry value for each recording medium.

FIG. 9 is a relationship diagram showing a relationship between a laser output when the digital still camera shown as an embodiment of the present invention writes data to a recording medium and an asymmetry value after the writing.

FIG. 10 is a relationship diagram showing a relationship between an asymmetry value at the time of writing and a recording jitter value calculated by the digital still camera shown as the embodiment of the present invention.

FIG. 11 is a flowchart illustrating a test writing operation process performed when the digital still camera shown as an embodiment of the present invention writes data to a recording medium.

[Explanation of symbols]

Reference Signs List 1 digital still camera, 10 image pickup device, 11 image signal operation processing unit, 12 display unit, 13 OP unit, 14
RF processing unit, 15 servo signal processing unit, 16 analog filter processing unit, 17 signal processing unit, 18 spindle driver, 19 thread driver, 20 tracking driver, 21 focus driver, 22 spindle motor, 23 thread motor, 24 temperature detection sensor, 25 control unit, 26 recording medium, 30 lens unit, 3
1. Charge coupled device, 32 S / H circuit, 33 A / D conversion circuit

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) H04N 5/225 H04N 5/225 F 5/85 5/85 Z (72) Inventor Hirokazu Kimura Shinagawa-ku, Tokyo 6-7-35 Kitashinagawa F-term (reference) in Sony Corporation JJ12

Claims (24)

[Claims] 1. An optical recording apparatus for recording data on a recording medium by optical recording, comprising: a writing unit for writing data on the recording medium; and a writing unit for writing the data on the recording medium. An optical recording apparatus comprising: a control unit for controlling whether to execute test writing. 2. The optical recording apparatus according to claim 1, wherein said control means executes test writing according to conditions. 3. The optical recording apparatus according to claim 1, wherein said control means executes test writing when data writing is the first writing to said recording medium. 4. An optical recording apparatus according to claim 1, wherein said control means executes test writing when data writing is the first writing after replacement of the recording medium. 5. The optical recording apparatus according to claim 1, wherein said control means executes test writing each time data is written a predetermined number of times. 6. The optical recording apparatus according to claim 1, wherein the control means executes the test writing when the writing is the first writing after a lapse of a predetermined time after the test writing. 7. The optical recording apparatus according to claim 1, wherein, when writing data, the control means executes test writing when a change in temperature of the environment has reached a predetermined amount. 8. The optical recording apparatus according to claim 1, wherein the control unit does not execute the test writing when the test writing area of the recording medium ends. 9. An optical recording method for recording data on a recording medium by optical recording, wherein when writing the data to the recording medium, it is controlled whether or not test writing is performed. Characteristic optical recording method. 10. The optical recording method according to claim 9, wherein the test writing is performed according to a condition. 11. The optical recording method according to claim 9, wherein if the data writing is the first writing to the recording medium, a test writing is performed. 12. The optical recording method according to claim 9, wherein when the data writing is the first writing after the exchange of the recording medium, the test writing is executed. 13. The optical recording method according to claim 9, wherein test writing is performed every time data is written a predetermined number of times. 14. The optical recording method according to claim 9, wherein, if the writing is the first writing after a lapse of a predetermined time from the test writing, the test writing is executed. 15. The optical recording method according to claim 9, wherein, when writing data, test writing is executed when a temperature change in the environment has reached a predetermined amount. 16. The optical recording method according to claim 9, wherein the test writing is not executed when the test writing area of the recording medium ends. 17. An image pickup means for picking up an image of a subject, an image processing means for processing picked-up image data, a recording / reproducing means for recording and / or reproducing data on a recording medium, and And a control unit for controlling whether or not test writing is performed when writing to the digital still camera. 18. The digital still camera according to claim 17, wherein said control means executes test writing according to conditions. 19. The digital still camera according to claim 17, wherein said control means executes test writing when data writing is the first writing to said recording medium. 20. The digital still camera according to claim 17, wherein said control means executes test writing when data writing is the first writing after replacement of the recording medium. 21. The apparatus according to claim 1, wherein said control means executes test writing each time data is written a predetermined number of times.
7. The digital still camera according to 7. 22. The digital still camera according to claim 17, wherein the control means executes the test writing when the writing is the first writing after a predetermined time has elapsed since the test writing was performed. 23. The control means, when writing data,
18. The digital still camera according to claim 17, wherein test writing is performed when a temperature change of the environment reaches a predetermined amount. 24. The digital still camera according to claim 17, wherein the control unit does not execute the test writing when the test writing area of the recording medium ends.