JPS6132730B2 - - Google Patents

Description

[Detailed description of the invention] The present invention relates to a recording/reproducing device.

Problems often arise in the relative synchronization between different information sources. For example, it is often the case that some tervision program sources are behind others by, for example, 1/2 field, or that the time relationships are gradually shifted, or both. Currently, there is no way to compensate for differences between these sources, so each source can only be used in the same program. There are several types of television systems in the world. The United States and Japan use the 525 line, 60 field/second MTSC system. In Europe, the 625-line, 50-field PAL system is common. There is no simple way to convert one frequency reference to another.

Additionally, equipment for delaying or "stopping" broadcasts, such as those using magnetic recording and reproducing devices, is relatively complex and expensive. Additionally, magnetic recording and playback generally requires a minimum delay between recording and playback so that separate recording and playback heads can be physically accommodated along the magnetic recording medium.

SUMMARY OF THE INVENTION An object of the present invention is to provide a device that can reproduce recorded information with a delay.

Another object of the invention is to provide an apparatus capable of recording and reproducing information at various speeds.

It is a further object of the present invention to provide an apparatus capable of information and delay recovery and in which the relative delays can be varied over a wide range.

Still another object of the present invention is to provide an apparatus capable of transcoding between different coding standards.

Still another object of the present invention is to provide a device capable of delaying and stopping reproduction of information.

According to the invention, first and second optical devices are arranged with respect to a recording medium suitable for receiving and recording electromagnetic information. The first optical device records information via the first optical path, and the second optical device reads the recorded information via the second optical path. The first and second optical devices have a predetermined simultaneous operative relationship with the recording medium, and the first and second optical devices are actuated dynamically and provide a variable delay between the recorded information and the read information. A device is provided to adjust the amount. This allows the second optical device to read the information at a predetermined delay time after the recording has taken place. Alternatively, a device can be provided for moving the first and second optical devices relative to each other, so that the reading speed is different from the recording speed.

Preferably, the first and second optical devices are provided with an optical scanning device that is simultaneously arranged on a recording medium on which information for reproduction is rapidly recorded by an optical recording means.

Preferably, the optical scanning device forms a track of information across the moving recording medium, such that the scanned information is divided into recording lines extending across the recording medium. In addition, an electronic device is provided that processes information according to the overscan gap between recording lines, that is, from edge to edge of the recording medium, and the information is compressed while recording to the recording line and read out at a predetermined speed. It is preferable to decompress the information.

The invention will be explained with reference to the drawings.

FIG. 1 is a side view of an example of the recording/reproducing apparatus of the present invention, particularly showing the scanning device portion thereof in cross section. Fig. 2 is a plan view of the recording/reproducing device shown in Fig. 1, and Fig. 3 is a plan view of the recording/reproducing device shown in Fig. 1.
FIG. 3 is a diagram illustrating the recording scanning device shown in the figure. Particularly with reference to FIGS. 1 to 3, the recording and reproducing apparatus of the present invention is provided with a first optical scanning device 10 and a second optical scanning device 12.
causes a beam of electromagnetic energy, such as a light beam, to be scanned across the recording medium 14. The recording medium 14 is preferably a tape that is fed from a reel 16, passes between capstan rollers 18 and 20 and between capstan rollers 22 and 24 in the direction of the arrow, and is wound onto a take-up reel 26. It is. The capstan rollers 18 and 22 are driven by servo motors 29 and 30 (FIG. 2), respectively, and each of these capstan rollers has a contoured surface for recessing the recording medium 14, as shown in FIG. is provided so that the light beam from the scanning device 10 is accurately focused onto the recording medium.

The recording medium must be of a self-developing type. There are several types of satisfactory photosensitive materials, such as those made of dry silver, those made of free radicals, those that are porous (culver), those that are thermally destroyed (melted or vaporized), and those that are thermally destroyed (melted or vaporized). There are photochromic things. When using dry silver and free radical photosensitive materials, other heat treatments are necessary if permanent recording is desired. For these materials, therefore, recording by the scanning device 10 is followed by a heating element (not shown). A variety of high speed optical recording media are known to those skilled in the art.

The scanning device 10 is provided with a metal cylindrical body 28, and the metal cylindrical body 28 is supported in a bearing 31 supported by an outer cylindrical body 32, and a motor coil 34 is also supported by the outer cylindrical body 32. It is preferable to Therefore, the metal cylinder 28 constitutes the rotor of a motor such as a synchronous hysteresis type.

A rotating head 36 is attached to one end of the metal cylindrical body 28.
A plurality of objective lenses 38 are held at the front periphery of this head 36. As shown in FIG. 3, six equally spaced objective lenses 38 are provided at the front end of the head 36 and within its sloping front wall so that the metal cylinder 28 is parallel to the direction of travel of the recording medium 14. When rotating around an axis, recording medium 1
The scanning can be performed across 4.

Light for the scanning device 10 is provided by a laser 40 that is arranged axially of the scanning device 10 and directs a light beam 42 substantially along the axis of the scanning device through a modulator 44 into an optical tube 46 . The optical tube 46
is preferably arranged within the metal cylinder 28.
The optical tube 46 is provided with lenses 48 and 50 and a pinhole 52 between these lenses. lens 50
directs light from the pinhole onto a pyramid-shaped mirror 54. The mirror 54 is secured to the front end of the head 36. This mirror 54 serves to sequentially direct light onto a plurality of lenses 38 as the head 36 rotates. Therefore, since six objective lenses 38 are disposed within the head 36, the pyramid-shaped mirror 54 is provided with six surfaces, and each of these surfaces sequentially reflects light to the lens 38, forming a light beam. 55 is recording medium 1
4 and scan across.

The light beam is imaged into a narrow track across the recording medium 14. The width of the recording track is approximately 1 micron, and the spacing between track centers as the recording medium 14 runs lengthwise is approximately 3 microns. The total track length required depends on the recording format and bandwidth chosen. Approximately 2 inches (1 inch is 2.54
cm), approximately 4.5 inches of recording medium are required per minute for television recording. That is, approximately 11 feet (1 foot is 12 cm) of recording medium is required for each 30 minute period. A 1000-foot reel of recording film lasts for about two consecutive days. This recording density is more than 100 times better than the recording density for television information on magnetic tape, for example.

The recording device according to the invention generally records information digitally, in which case the modulator 44 is in the on state when controlled by a binary input on a conductor 56 connected via an amplifier 58 to the modulator 44. Or it will be in an off state. In such a case, the type of recording described in US Pat. No. 3,501,586 is performed, ie, the information is represented by digital spots. However, the device according to the invention is also suitable for recording analog information, in which case an analog input is provided on conductor 56.

According to the recording and reproducing apparatus of the present example, a second or reading scanning device 12 is disposed along the recording medium, and the recorded information is recorded at a variable preselected time after the information is recorded on the recording medium. to be read. This second scanning device 12 is substantially identical to a recording and scanning device, and includes a cylindrical body 60 supported in a bearing 62 fixed to an outer cylindrical body 64. Thus, the motor coil 66 is also supported. The head 68 also supports a pyramid-shaped mirror 70 at its front end.
The mirror 70 directs the light through a plurality of objective lenses 72 in the sloping front wall of the head. The number of objective lenses 72 can be the same as the number of objective lenses 38 in the recording scanning device, ie six in this example.

A reproducing laser 74 supplies a light beam through an optical tube 76 having lenses 78 and 80 arranged along the axis of the scanning device 12 and a pinhole 82 located between the lenses. Lens 80 directs the light beam passing through pinhole 82 onto pyramid-shaped mirror 70 which sequentially directs the light beam in the direction of a particular objective lens 72 that is being scanned across recording medium 14. .

A pinhole 82 and a lens 80 are located inside the optical tube 76.
Another deflection device 84 is housed between the two. This deflection device is a U.S. patent application filed on November 11, 1974.
It is described in the specification of No. 522702. A typical example of this deflection device is shown in FIG. Light is lens 78
Optical fiber 8 shown in end view from FIG. 1 to FIG.
6 axis. optical fiber 86
are preferably deflected in mutually perpendicular directions as indicated by arrows 88 and 90. The first coil 92 is provided on a first metal magnetic core, and magnetic pole pieces 94 and 9 are located on both sides of the optical fiber 86 with both ends of the magnetic core.
6. The second metal magnetic core has magnetic pole pieces 98 and 100 arranged on both sides of the optical fiber 86 and along a direction perpendicular to the direction in which the magnetic pole pieces 94 and 96 are connected, and around the second metal magnetic core. A second coil 102 is arranged at. optical fiber 8
6 is made of transparent glass or plastic and provided with a coating made of metal or other conductive material,
One end of this coating is connected to the battery 106 by a conductive wire 104.
electrically connected to one electrode of this battery 106
Ground the other electrode. The other end of the coating on the optical fiber is also grounded to allow current to flow along this coating. The first ends of the coils 92 and 102 are connected to a tracking controller 108 which selectively applies current to the coils 92 and 102 to deflect the optical fiber 86 by a desired amount. In this way, lens 7
Accurate positioning of the light beam irradiated onto the recording medium 14 via the optical system 2 can be controlled. Other structures of deflection devices are described in the above-mentioned U.S. patent application Ser. . The purpose of this deflection arrangement, which will be explained in more detail below, is primarily to cause the light beam 110 to follow a particular recorded track across the recording medium 14.

As the light beam 110 follows a line or track of recorded information, a variable amount of light is transmitted through the recording medium 14. The luminous intensity of the laser 74 is set to such an extent that no other recording occurs. The transmitted light is collected by a fiber optic condenser tube 112 extending below the path of the light beam 110, which concentrator tube supplies light to a detector 114 having an optoelectronic device. produces an output 116. The detector is provided with a follow-up control device exhibiting the function of the follow-up control device 108 shown in FIG.
U.S. Patent Application No. 483131 filed June 26, 1974
It can be of the type described in the specification. Alternatively, a tracking circuit of the type described in US Pat. No. 3,501,586 may be used, in which the back and forth movement of the light beam 110 across the recorded track is detected. In any case, the conductor 1 is connected to a servomechanism drive circuit 120 and 122 respectively connected to the deflection device 84 and to a motor 124 for driving the scanning device 12 along the recording medium 14 as will be explained in more detail below.
A servo output is generated at 18. The deflection device 84 is controlled by the servomechanism drive circuit 120, and the recording medium 1
The light beam 110 is directed to follow the previously recorded track across the track 4. An integrator circuit 126 also drives the servomechanism drive circuit 120 to the servomechanism drive circuit 122 so that the average or long-term error from the intended beam position causes the motor 124 to move the scanner 12 physically relative to the scanner 10. Make sure to move the target. Deflection device 84 causes light beam 110 to follow the recorded track despite slight errors in recording medium movement, scanning device movement, vibration, etc.

With particular reference to FIG. 2, the scanning device 12 is mounted on a bracket 128 that is slidable on a fixed rail 130 parallel to the path of the recording medium 14. Motor 124 rotates a lead screw 132 that engages a corresponding threaded hole portion in bracket 128, and rotation of lead screw 132 physically moves scanning device 12 in the longitudinal direction of recording medium 14. Also, an axis encoder 135 that indicates the position of the scanning device 12 with respect to the scanning device 10 by rotation of the motor 124.
Rotate.

The first function of the above-described device is to perform delayed reproduction of information recorded on the recording medium 14. By positioning the scanning device 12 along the fixed rail 130, a predetermined amount of delay can be created for recording, from approximately zero delay during playback to a delay of several minutes or more. For this reason,
It is clear that when moving into a substantially contact position with respect to the scanning device 10, the light beam 110 can be focused on the recording medium 14 to a point that substantially coincides with the recording beam 55. In the case of a magnetic recording/reproducing device, the above-mentioned free range regarding reproduction timing cannot be obtained. The reason for this is that the magnetic write head and magnetic read head must be close to the recording medium, thereby creating a minimum delay between recording and reading.
In other words, the magnetic write head and the magnetic read head cannot be co-located and mechanical disturbances will inevitably cause a delay in reading out what has been recorded. However, in the case of optical writing and reading, it is possible to direct the reading beam in the direction of approximately the same location on the recording medium where the writing occurred, or at any selected location after writing. can.

On the other hand, in the apparatus of the present invention, the recording density is extremely high, and the relative movement of the scanning device 12 away from the scanning device 10 causes a considerable delay. The device of the invention is suitable for use in producing a desired delay during playback, or for playing back information at a speed different from the speed at which the information was recorded.
For this reason, the scanning device 12 is connected to the servomechanism drive circuit 1.
22 along a fixed rail 130 to produce the desired output speed. The head 68 is rotated under the control of a servomechanism drive circuit 134 coupled in driving relation to the motor coil 66 (FIG. 1) and responsive to an external clock signal so that the scanning device 12 can scan the recorded tracks in response to the external clock signal. Scanning is performed sequentially at a speed according to the signal. Briefly, servomechanism drive circuit 120 causes deflection device 84 to keep beam 110 on track. Continuous deviations of the deflection device 84 from the "normal" position result in a continuous output from the servomechanism drive circuit 120 through the integrator circuit 126, causing the servomechanism drive circuit 122 to
24 to gradually move the scanning device 12 in a desired direction. When the scanning speed of the reading scanning device 12 is made slower than the scanning speed of the recording scanning device 10, the scanning device 12 is gradually moved to the left in FIG. 2, that is, in a direction away from the scanning device 10. Generally, the distance that the scanning device 12 is mechanically moved for this purpose does not need to be very long, so the amount of movement of the scanning device 12 given for the above-mentioned purpose (delay, etc.) is sufficient to achieve the scanning speed. Movement for difference can be achieved. Alternatively, two devices as described above may be used alternately, such that the scanning device 12 of the second device takes over reading out the recorded information while the scanning device of the first device returns to its original position. be able to.

The opposite situation occurs if the information is being read out at a faster rate than it was stored, and the scanning device 12
always moves in a direction closer to the scanning device 10. In this case as well, two devices may be used, with the first reading scanning device being moved away from its recording scanning device 10 while the second reading scanning device is reading.

Alternatively, instead of using multiple recording and reproducing devices, information may be skipped in some cases.
Alternatively, a single device that repeatedly plays the information can be used. Therefore, in the case of television recording, staggers can be accumulated for each frame. Axial encoder 135 senses scheduled physical movement of scanning device 12 in one or the other direction and determines approximately when one frame of error has accumulated. Controller 292 controls deflector 84 to move light beam 110 along the tape a distance of one recording frame. Preferably, each scan line across the recording medium 14 has 25 television horizontal raster lines, so that in an NTSC system of 252 horizontal raster lines, there are 21 scan lines on the recording medium per frame. There is. In the case of the PAL system, the above-mentioned 25 scanning lines exist on the recording medium per frame.
Deflection device 84 is servo-driven by servomechanism drive circuit 120 to move it backwards or forwards by a predetermined amount depending on the direction of the accumulated error. The actual scanning movement for skipping a frame or for repeating a frame can be made to occur simultaneously with the end of the frame detected by the detector 114 and supplied to the controller 292.
Because of this, the light beam 110 is locked in a different track than the "normal" position relative to the deflection device 84, so that the servomechanism drive circuit 120 controls the servomechanism drive circuit 122 via the integrator circuit 126 and the scanning device 12 in the opposite direction. In the above description, skipping or repeated reproduction of one frame has been described, but if desired, the apparatus of the present invention may skip or repeatedly reproduce more than one frame or other predetermined amount of information. It is clear that this can be done.

The device of the present invention is useful for transformer synchronization, that is, for example, when coupling one television signal to a device that lags behind another device by 1/2 field (i.e., there is a drift relationship between these devices). It is. The synchronization signal is the scanning device 1
0 in response to its own input data clock signal which properly controls the rotational speed and is synchronized with a desired output clock signal which controls the servomechanism drive circuit 134, for example as described with respect to the circuit of FIG. to play.

To transcode, ie convert from one television standard to another, television signals of different standards are recorded by a scanning device 10 and converted to the desired standard by a scanning device 12. Play in sync with. The frequency standard problem can be handled in the same way as in the transformer synchronizing case described above. For cosmetic purposes, it is desirable to provide the output conductor 116 with the circuit of FIG. 11 so that the lines can be repeated as necessary to fill gaps between lines. Since the PAL system has a large number of scanning lines, it is desirable to add lines when converting from the NTSC system to the PAL system. Referring to FIG. 11, delay line 293 is preferably provided with a digital register having a length capable of holding data for one television horizontal raster line. Both delayed and non-delayed outputs are provided to a select and add circuit 294. When converting from NTSC to PAL, circuit 294 selects a predetermined input raster line, for example the first raster line, in a non-delayed manner. For the second output raster line, circuit 294 selects the sum of the information available from the delay circuit path and the non-delay circuit path. For the third output raster line, controller 292 directs scanning device 12 by repositioning deflection device 84 to rescan the second input frame. The third input raster line is then read out via circuit 294 without delay. Alternatively, the horizontal raster lines can simply be stored and repeated, or the output can be varied analogously.

When converting from PAL system to NTSC system (transcoating), selection and addition circuit 294
You can remove some horizontal raster lines using To fill gaps caused by skipping lines, lines can be summed using a circuit of the type shown in item 11. For example, a predetermined input raster line, eg, a first input raster line, is selected without delay by circuit 294. The second input raster line is skipped,
A circuit 294 adds the first input raster line delayed by the third input raster line to the second output raster line. Next, the fourth input raster line is set as the third output raster line, and so on. To prevent the image from being compressed vertically, various portions of each horizontal raster line can be randomly removed. Horizontal raster lines can be stored for this purpose and selected portions thereof can be removed using logic.

To skip lines, it is desirable to change the position of the deflection device 84 of the scanning device 12 so that the flow of output information is continuous regardless of the deletion of information. Alternatively, a first-in, first-out (FIFO) memory of the type described in more detail below may be used to convert a discontinuous stream of data into a continuous stream of data. There are various methods for cosmetically converting transcoated data, and these methods are well known to those skilled in the art.

The device according to the invention can obviously be used to delay normal live television broadcasts for any period up to a few minutes. This is useful in live program presentations in that the director can preview the broadcast seconds or minutes before transmission. Furthermore, according to the device of the present invention, a "stopping operation" can be easily performed. Deflection device 84
controls to reread one predetermined frame or a predetermined series of frames. In this case, the deflection device 84 moves the light beam 110 along the recording medium 14 almost instantaneously. Deflector 84 is controlled by controller 292 via servomechanism drive circuit 120 to repeatedly play a desired portion of the tape for periods of up to several minutes, thereby providing a stop operation or instantaneous repeat play. With each repeat, the deflection device 84 moves away from its normal position, thereby commanding the servomechanism drive circuit 122 via the integration circuit 126 to move the scanning device 12 away from the scanning device 10. Because of this repetitive playback type operation, a slow integration circuit can be used to prevent scanning device 12 from reciprocating too much along the recording medium.

The device of the present invention can be used, for example, for indexing and editing purposes when recording information is in digital form. In such a case, it is preferable that the control device 292 is provided with a small computer, which counts the frame tracks and maintains them on the recording medium. Servomotors 29 and 30 (FIG. 2), operating under the control of servomechanism drive circuit 288, advance or move the recording medium over the entire span of the tape held by reels 16 and 26, for example. It is suitable to run at different speeds in the reverse direction and under the supervision of a controller 292 (FIG. 1) which determines the position of a certain frame. An editor monitoring a television monitor or the like receiving input from output conductor 116 may play back a segment of the recording medium at any speed, e.g., in slow motion, or frame sequentially, and select the exact frame desired. Select. Each frame can be marked or pre-marked on the recording medium with various numerical representations, and the frames can be calculated and stored relative to one another under computer control. Once the segments for the entire program have been found and selected, these segments can be re-indexed and read sequentially into another recording device, preferably a duplicate of the device of FIGS. I can put it out. Each device can operate on a start-stop basis. In this case, the recording medium is brought to a predetermined speed within one frame time (30 milliseconds) and the deflection device 84 is used to compensate for tape acceleration so that starting and stopping are instantaneously effective. That is, the deflection device 84 is controlled together with the movement of the recording medium 14,
Deflection device 84 until the recording medium reaches a predetermined speed.
sweeps the recording track.

A speed sensor 290 coupled to the servomechanism drive circuit 288 is preferably provided to measure the movement of the recording medium. If monochromatic light is used, the velocity detector may be, for example, light sensitive and responsive to Doppler frequency shifts.

FIG. 5 shows another example of the recording/reproducing device of the present invention,
Such a recording and reproducing apparatus is provided with a disk-type recording and scanning device 136 and a disk-type readout and scanning device 138, and a film or a plurality of plates 190 on which information can be recorded in substantially the same manner as the recording medium 14 of the above-mentioned example. , 192 are disposed on both sides of the recording medium, respectively. However, in this example, the recording track that traverses the recording medium is not substantially straight as in the previous example, but is arcuate. The scanning device 136 includes a plurality of objective lenses 142 evenly spaced around its periphery and a laser 150.
A disk portion 140 is provided that carries an internal mirror 144 that directs a light beam from the disk toward the recording medium to form a beam 154 at the recording medium. Scanning device 136 is further provided with a shaft 146 that holds disk portion 140 and is rotated by motor 148 . This axis 146 is provided with distributing mirrors 145 located around it, such that each distributing mirror directs the light beam originating from the laser 150 through an internal reversing mirror 144 and onto one of the lenses 142 . Modulator 152 is provided with an input signal.
For this reason, the mirror 144 has a shaft 146 connected to the motor 1.
When rotated by 48, it sequentially records tracks across the recording medium.

Information recorded on recording media 190, 192 is read by scanning device 138. This scanning device 13
8 includes a motor 16 held by a shaft 164;
A disk portion 156 is provided which is rotated by 6. A plurality of lenses 158 are provided near the periphery of the disk portion 156, and these lenses direct the readout beam to the recording media 190, 192.
irradiate. This readout beam is generated by a laser 174, passes through a deflection device 176, and is directed onto one of the light distribution mirrors 162 rotating with the shaft 164. These mirrors 162 sequentially reflect the readout beam so that the reflected beam passes through mirror 160 and then through one of the lenses 158. Deflection device 176 is suitably of the type shown in FIG.

The scanning device 138 is rotatably supported by an outer case 168, which houses a motor 166, a laser 174, and a deflection device 176. The outer casing 168 is connected to the outer casing by screws and a motor 184 is connected to the outer casing 168 .
It can be moved along a rail 172 by actuation of a lead screw 170 rotated by. outer box 16
8 is fitted with a detector 188 moving therewith, which, in addition to generating an output of recorded information, generates an input to a servomechanism drive circuit 178 in control relationship with the deflection device 176. . Additionally, an integrating circuit 180 couples a servomechanism drive circuit 178 to a servomechanism drive circuit 182 which rotates a motor 184 and thus moves the housing 168 and moves the scanning device 138 onto the track. Hold.
The motor 184 is further provided with a digital shaft encoder 186 for providing a feedback signal. The present device operates in substantially the same manner as the previously described example, and is provided with other control circuits for use in conjunction as in the previously described example.

The example of FIG. 5 further includes an axis of the scanning device 136.
An input laser 150' and an input modulator 152' can be provided on the opposite side from elements 150 and 152. The scanning device 138 can likewise be supplied with a light beam originating from an additional laser 174' and deflected via a deflection device 176'. Additionally, additional detectors 188' may be provided. By switching both recording lasers and both reproducing lasers, the recording scan and the read scan can be switched from the first recording medium or plate 190 to the second recording medium or plate 192 without interruption, thereby allowing the fixed Continuous recording and playback can be performed with the plate device. When reading with a certain delay time after recording,
Of course, the reading laser is operated after the recording laser.

Still another example of the device of the present invention is shown in FIG. The apparatus of this example includes a recording scanning device 194 and a reading scanning device 196 that are concentric with each other. Scanning device 19
4 has an upper disk portion 198, and this disk portion 198 has an objective lens 2 near its periphery.
10 and separate lenses 21 for scanning the recording medium 197 with light from the laser 204.
A pyramid-shaped mirror 208 is provided to reflect the light to zero.
Light from laser 204 is modulated by modulator 206 and passed through hollow shaft 200 of scanning device 194 . This shaft 200 is rotated by a motor 202. The readout scanner 196 includes a lower disk portion 212 which holds a lens 220 near its periphery and which directs the laser 2
22, passes through a deflection device 224, preferably of the type of FIG.
The light reflected by lens 220 is
It depends on the individual. A shaft 214 supporting disk portion 212 is rotated by motor 203 . A readout beam is formed by a lens 220, and the light passing through the recording medium 197 is guided to a detector 230 and collected by an optical fiber device 228.
Generates output from 0. Detector 230 further activates servomechanism drive circuit 232 which causes deflection device 22 to operate as described above.
Control 4.

Also in the example of FIG. 6, one recording medium 1
Instead of using 97, multiple recording media, ie, multiple plates, can be used, as shown at 190 and 192 in the example of FIG. It is also possible to modify the structure of FIG. 6 and provide another set of recording and reproducing lasers similar to the additional lasers of FIG. 5 to provide continuous recording and reproducing with a fixed plate arrangement. can.

Since the two scanners in the example of FIG. 6 are concentric, little relative physical movement is allowed between the two scanners. However, the deflection device 224
is suitably controlled by the controller 233 so that the readout beam reads the recorded track with a predetermined delay following the recording, or the readout is performed at a different speed than the recording. Do it like this. Although the possible delays are somewhat more limited in this example than in the example of FIG. 5, this example is of course a simpler structure than the example of FIG.

The operation and various functional characteristics of the deflection device, detector and control device of the example of FIGS.
It is suitable that it be substantially the same as that described in connection with the example in Figures 3 to 3.

Because of mechanical imperfections, it is desirable to provide an "overscan" portion on each side of the recording medium, such as shown at 14 in FIG. This means that the recorded data is recorded in a raster fashion in parallel lines across the tape, but the edges of the lines do not coincide with the edges of the tape, and each line is precisely relative to the next. This means that they are not juxtaposed. Figures 7 and 8 take a continuous stream of data (Figure 7), divide the data stream into multiple scan lines across the tape, and piecewise time compress each scan line. A circuit is shown that provides a small gap between the next scan line. This causes each segment of information to be sped up or compressed relative to time, creating a time gap between each segment. When reproducing, or reading out, information, this information is expanded so that gaps no longer exist.

FIG. 9 shows recording of television information. In FIG. 9, 264 indicates one horizontal television line (raster line), and this horizontal television line has digitized information 265.
A horizontal blanking pulse is also shown at 266. Additionally, an overscan gap is indicated at 268. This overscan gap can (in some cases) constitute a direct blanking period. A plurality of television raster lines are provided for a given scan line of information across the tape.

FIG. 10 shows a recording medium 14 in the form of a tape, which is generally transparent except for a plurality of recorded lines or tracks 284 that can be recorded by the scanning device 10 shown in FIGS. 1-3. do. As previously mentioned, the recorded information may actually be in the form of closely spaced digital spots in the line. Also, the scanning line or track 2
84 are also spaced very closely apart as described above. The scan line is scanned across the tape by successive lenses 38. In this case, the scan line crosses the tape diagonally because the tape is moving as the scan is performed. The starting point of the next scan is immediately across the tape from the ending point of the previous scan. This allows the scanning device used for reading to easily be in the correct position for each subsequent scan. The overscan gap corresponds to a short period of time between the end of a given scan across the tape and the beginning of the next scan.

Referring to FIG. 7, a data input signal and an input clock signal are provided to a first-in/first-out memory 234. This memory 234
requires multiple Fairchild 3341s connected in parallel.
(Product name) type MOS type integrated circuit can be provided. This memory 234 is connected to an AND gate 238
from this AND gate when it receives a horizontal sync pulse, a vertical sync pulse, and a scanner start indication signal that indicates that the scanning beam is approximately at the beginning of the digital scan line, as will be explained in more detail below. It is reset by the resulting output signal. Similarly, the up/down counter 236 is also reset by the output signal of the AND gate 238. During the overscan gap, ie, the gap between recording lines across the tape, input information is provided from the data input lead to memory 234 at a rate determined by the input clock signal. At the same time, the up/down counter 236 to which the input clock signal and the output clock signal are supplied performs calculations in an incremental (additive) manner. However, the up/down counter 236
No information is read from the memory 234 until the count has reached a full count state indicating that the memory 234 is full. When counter 236 reaches its full count state, the output signal F of counter 236 triggers flip-flop 240 on, enabling AND gate 244. On this occasion
A clock signal from a clock signal generator 242 coupled to the memory 234 via an AND gate 244 causes the memory 234 to output a data output signal to a recording device, such as the input lead 56 of FIG.
to be supplied to The rotation of the head 36 is controlled so that the recording beam emanating from one of the lenses 38 is located just inside the edge of the recording medium 14 at this instant. To this end, the scanner start signal to gate 238 is derived from a detector 286 (see FIG. 2) responsive to a mark on head 36.
The gate 238 is enabled at the start of the overscan, ie when the scanning beam 55 is at a position where the data would normally start without being time compressed. This position also corresponds to the end of the previous scan line 284. The speed of the recording motor is locked to the aforementioned input clock signal.

During a scan line, an output clock signal taken from clock signal generator 242 via gate 244 is applied to up/down counter 236 to step down the count of counter 236. This clock signal is supplied until the counter 236 reaches an empty count state indicating that the memory 234 is empty. When this empty count condition is reached, output signal E of counter 236 turns off flip-flop 240 so that gate 244 is no longer enabled and another overscan interval occurs. The output of clock signal generator 242 is also provided to divide-by-N counter 250 via gate 248. N here
means the number of clock bits per scan line across the tape. This number N is also the number of bit positions in one scanning line in the case of digital recording. Therefore, counter 250 provides an output to phase lock detector 246 at the end of one scan line. The output of this counter 250 is fed to the inhibit terminal of gate 248, blocking the input to this counter. At the same time, since the memory 234 finishes processing (runs out) at the end of one scanning line, the up/down counter 236 supplies an empty count state signal to the phase lock detector 246 at the end of one scanning line. If the pulse edges of the two counters 236 and 250 supplying their input signals to a phase lock detector 246 do not match, the phase lock detector 246 generates an analog signal that generates a clock signal. 242 to the proper frequency so that the proper phase is obtained at the end of each scan line, thereby producing the desired overscan gap and desired data flow. Counter 250 indicates the start of a scan line.
It is reset by the total count output of down counter 236.

FIG. 8 shows a circuit for reading out scan lines with overscan gaps between each other to produce continuous output necessary for audio, video, and other purposes. The data input signal is sent to a regenerative detector, e.g. detector 1 in FIG.
14 via an output conductor 116. An input clock signal generator 272 synchronizes the data from the recording medium. That is, the input clock signal generator 272 is connected so that a synchronizing signal is supplied from the detector 114, for example. The output clock signal provided to memory 252 and up/down counter 280 is suitably derived from a standard oscillator, such as a color reference signal crystal oscillator in a color television receiver.

Memory 252 is preferably a first-in, first-out memory similar to the memory of FIG. In addition to feeding the data from the replay detector to the memory 252, it is also fed to a data start detector having a diode 254 coupled to the input terminal of an amplifier 262. In this case amplifier 262
The input terminal of the capacitor 256 and the resistor 25
It is shunted to the ground by a parallel circuit consisting of 8 and having an integral function. A second input terminal of amplifier 262 is connected to an adjustable tap of potentiometer 260;
Both ends of this potentiometer are connected to a suitable voltage source to adjust the sensing level of the circuit. The cathode of diode 254 is connected to the amplifier input terminal so that the positive going signal at the end of overscan gap 268 in FIG. 9 produces an output signal from amplifier 262 that resets flip-flop 270. do. amplifier 26
The inputs and outputs of 2 remain positive for the duration of the scan line, i.e. until the arrival of the next overscan gap 268, at which time the amplifier 262 is reversed depending on the setting of the potentiometer 260. Be biased. The charge on capacitor 256 is thus dissipated in resistor 258 and the circuit is ready to wait for a positive going signal at the end of the overscan gap.

At the beginning of data, the output of amplifier 262 causes memory 252 to
and resets counters 278 and 280.
Flip-flop 270 is AND gate 274
, thereby causing AND gate 274 to provide clock pulses originating from clock signal generator 272 to memory 252 so that the data input is written to this memory. During the scanning line, information is supplied to the memory 252 earlier than during reading, and the counter 2 receives the input clock signal and the output clock signal supplied to the memory 252.
80 detects when memory 252 is full, at which time counter 280 registers with phase lock detector 282.
supply the output to. Also during a scan line, a divide-N counter 278, which receives a signal from the clock signal generator 272 via gate 276, calculates the number of clock bits per scan line and provides an output to the phase lock detector 282 at the end of the scan line. This output is also provided to the inhibit terminal of gate 276 to block the input to the phase lock detector. Two counters 278 fed to phase lock detector 282
If the pulses at the output of A constant output from the data conductor from the circuit of FIG. 8 is provided to ensure that data is provided at the correct rate.

When using an overscan gap as described above, the gap period can be used to provide an index mark at the edge of the tape for speed sensing by speed detector 290. When such an index mark is provided by a light beam, it is suitable to provide the speed detector 290 with a light source, such as a laser or a light detection device. As mentioned above, the provided index marks can be used for editing purposes.

The apparatus of FIGS. 7 and 8 for compressing and decompressing data can be used primarily to make the recording position in the direction of the data line less critical. This problem is not limited to devices that simultaneously record and read delayed data, but is also important for devices that use the same scanning device at different times for recording and reading, for example, and applies generally to this type of recording. Therefore, if continuous information such as a television raster is divided into separate segments for recording, the above-described arrangement prevents loss of information and simplifies synchronization problems. It is not necessary to use the overscan gap circuit of FIG. 7 to form the overscan gap, but only the output circuit of FIG. 8 is used. For example, when recording a television signal, the scanning of the television camera may be controlled appropriately so that the television camera sweeps slightly faster than normal for 25 horizontal raster lines and then stops for a certain amount of time. It can be done. Alternatively, using a delay device (not shown),
The first half of a given digital line can be stored and then this first half recorded simultaneously with the second half, ie spatially multiplexed. Of course, if the recorded data are not temporally related, ie not continuous, overscan gaps can be inserted without using the first-in/first-out memory.

In the example of a dual-scan device that uses separate scanning devices for writing and reading information, the effects of overscan gaps can be obtained in other ways without using the compression circuit of FIG. That is, the recording is performed by the recording scanning device without compressing the information. A longer scan than the recording is then performed by a scanning device for reading the information, preferably having a larger diameter than the scanning device for recording. In other words, the lines of information recorded across the recording medium are scanned faster than in recording, so that there is an effective gap between each scanned line with respect to the readout signal. This information can then be decompressed using the circuit of FIG.

It is clear that when digital information is recorded in scanning lines on a recording medium according to the invention, these scanning lines can be provided with opaque spots on a transparent recording medium or transparent spots on an opaque recording medium. It is.

It goes without saying that the present invention is not limited to the above-mentioned examples and can be modified in various ways.

[Brief explanation of the drawing]

FIG. 1 is a diagrammatic side view showing an example of the recording/reproducing apparatus of the present invention, with a part thereof shown as a cross section, FIG. 2 is a plan view of the apparatus shown in FIG. 1, and FIG. 4 is a diagram showing an example of the optical deflection device used in the present invention, and FIG. 5 is a diagram showing another example of the recording/reproducing device of the present invention. FIG. 6 is a diagrammatic side view showing another example as a cross section; FIG. 7 is a diagrammatic side view showing another example as a cross section; FIG. FIG. 8 is a block diagram showing an example of an electric circuit suitable for use in reproducing information according to the present invention. FIG. 9 is a block diagram showing an example of an electric circuit suitable for use in reproducing information according to the present invention. FIG. 10 is a plan view of a recording medium according to the invention, and FIG. 11 is a block diagram showing additional circuitry that can be used in television transcoding operations. 10, 12, 136, 138, 194, 196
...scanning device, 14,190,192,197...
...Recording medium, 28,60...Cylindrical body, 29,30
... Servo motor, 31, 62 ... Bearing, 32,
64... Outer cylindrical body, 34, 66... Motor coil, 36, 68... Head, 38, 72, 14
2,210...Objective lens, 40,74,15
0,150',174,174',204,222
...Laser, 42,55,110...Light beam,
44, 152, 152'...Modulator, 46, 76
...Optical tube, 48, 50, 78, 80, 82',
158,220...Lens, 52,82...Pinhole, 54,70,144,145,160,
162, 208, 216, 218...Mirror, 5
8...Amplifier, 84, 176, 176', 224
... Deflection device, 86 ... Optical fiber, 94, 96,
98,100...Magnetic pole piece, 108...Following control device, 112...Condensing tube, 114,188...Detector, 120,122,134,296,178,
182, 232, 288... Servo mechanism drive circuit, 124, 148, 166, 203... Motor, 126, 180... Integrating circuit, 128... Bracket, 130, 172... Rail, 132,
170... Feed screw, 135, 186... Shaft encoder, 140, 156, 198, 212... Disk portion, 168... Outer case, 283, 292...
...Control device, 234,252...First-in/first-out memory, 236,280...
...up/down counter, 238, 244, 2
74...AND gate, 240,270...Flip-flop, 242,272...Clock signal generator, 246,282...Phase lock detector, 248,276...Gate, 250,278
...N division counter, 286, 290...detector, 293...delay line, 294...selection and addition circuit.

Claims (1)

[Scope of Claims] 1. A recording medium capable of recording electromagnetic information, a first optical device for recording information along a track on the recording medium through a first optical path, and a first optical device that records information along a track on the recording medium through a second optical path. The second to read the recorded information along
an optical device, and these first and second optical devices are operated simultaneously on the same recording medium, and the first and second optical devices are operated simultaneously on the same recording medium, and
and a second optical device is arranged to simultaneously record information on the track and read information on the track, and the first optical path is positioned at a predetermined position relative to the second optical path. What is claimed is: 1. A recording/reproducing apparatus comprising: a control device for causing the recorded information to occupy a predetermined amount of time and applying a variable delay to the read information at a predetermined instant with respect to the recorded information. 2. In the recording and reproducing apparatus according to claim 1, the control device includes a drive device that moves the first and second optical devices relative to the recording medium, and a drive device that controls the drive device. and a servo device for adjusting the first and second optical devices so that they operate simultaneously at the same or different scanning speeds.