JP4902009B2 - Camera head separation type camera device and control method thereof - Google Patents

Description

  The present invention relates to a camera head separation type camera device in which a camera head and a camera control unit for controlling the camera head are separated, and a control method therefor.

  2. Description of the Related Art Conventionally, a camera head having an image sensor such as a CMOS is detachably connected to a camera control unit (hereinafter referred to as CCU (camera control unit)) that controls the operation of the camera head via a camera cable. A separate camera is known. Such a camera head separation type camera is used, for example, as a medical or industrial endoscope.

  In the camera head separation type camera device, the video signal obtained from the image sensor in the camera head is sent to the CCU by a dedicated cable. In recent years, video signals have been digitally transmitted by LVDS (Low Voltage Differential Signaling) signals with higher resolution and higher speed. LVDS is said to enable signal processing with high-speed transmission, small signal amplitude, low power consumption, and low electromagnetic interference.

  When a digital video signal is transmitted from the camera head to the CCU, there is a problem that it is difficult to correctly transmit the digital video signal when the transmission distance becomes long. As a method of solving this problem, based on the signal level of the reference signal transmitted through the specified transmission line, the transmission line is made to compensate for the deterioration of the frequency characteristics of the digital video signal by this transmission line. It has been devised to correct in advance the frequency characteristics of a digital video signal transmitted to a transmission target (see, for example, Patent Document 1).

JP-A-8-317251

  When transmitting a video signal from the camera head to the CCU as an LVDS signal, if the cable length is long, the amplitude of the differential signal decreases due to a voltage drop due to the internal resistance of the cable, and the rise time and fall time of the differential signal due to frequency characteristics The phenomenon that the time becomes longer occurs. Therefore, there is a problem that the CCU does not satisfy the data reproduction condition and cannot transmit accurate information.

  FIG. 13 is a schematic diagram of the waveform of the LVDS signal. If a plurality of LVDS signals continue at the same rising (falling) timing or voltage, the waveform is of good quality and the eye mask 60 is said to be “open”.

  FIG. 14 is a schematic diagram of the waveform of an LVDS signal with poor quality. As the cable length increases, the amplitude voltage of the differential signal decreases, and the attenuation of the high frequency component of the data due to the frequency characteristics, that is, the rise (fall) time of the data increases. As it invades, the eye closes as a result.

  The present invention has been made in view of the above circumstances, and can stably transmit an LVDS signal from a camera head to a CCU regardless of the length of a cable, and can output a stable video. It is an object of the present invention to provide a camera head separation type camera device and a control method thereof.

  In order to achieve the above object, the camera head separation type camera apparatus of the present invention is a camera head separation type camera apparatus in which a camera head and a camera control unit are connected by a cable. Control means for transmitting a DC (Direct Current) voltage is provided, and the camera head controls an LVDS conversion driver for transmitting an LVDS (Low Voltage Differential Signaling) signal to be transmitted to the camera control unit, and the LVDS conversion driver unit. An LVDS control unit and a correction control unit that outputs a correction value of an LVDS signal supplied to the LVDS control unit are provided.

  The camera head separation type camera apparatus according to the present invention is a camera head separation type camera apparatus in which a camera head and a camera control unit are connected by a cable. The camera head transmits an LVDS (Low Voltage Differential Signaling) to the camera control unit. ) For switching the correction value, an LVDS conversion driver unit for transmitting a signal, an LVDS control unit for controlling the LVDS conversion driver unit, a correction control unit for outputting a correction value of an LVDS signal supplied to the LVDS control unit, And a switch.

  According to the present invention, in the camera head separation type camera device and the control method thereof, the LVDS signal can be stably transmitted from the camera head to the CCU regardless of the length of the cable, and a stable image can be output. it can.

1 is a block diagram showing the configuration of Embodiment 1 of a camera head separation type camera apparatus according to the present invention. The figure which shows the example of the eye mask of a LVDS signal waveform. The figure which shows the example of the waveform of the state by which correction was added to the LVDS waveform. The figure which shows the example of the table of the relationship between a voltage drop and a correction value. The flowchart which showed the example of operation | movement of a camera head separation type camera apparatus. FIG. 6 is a block diagram illustrating a configuration of a camera head separation type camera apparatus according to a second embodiment. FIG. 10 is a diagram illustrating an example of a table of a relationship between a voltage drop and a correction value according to the second embodiment. FIG. 9 is a block diagram illustrating a configuration of a camera head separation type camera apparatus according to a third embodiment. FIG. 6 is an overview diagram of a camera head separation type camera apparatus according to a third embodiment. FIG. 10 is a diagram illustrating an example of a table of a relationship between switch setting values and correction values according to the third embodiment. FIG. 9 is a block diagram illustrating a configuration of a camera head separation type camera apparatus according to a fourth embodiment. FIG. 10 is a diagram illustrating an example of a table of a relationship between switch setting values and correction values according to the fourth embodiment. The schematic diagram of the waveform of a good quality LVDS signal. The schematic diagram of the waveform of LVDS signal with bad quality.

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

  FIG. 1 is a block diagram showing the configuration of Embodiment 1 of a camera head separation type camera apparatus according to the present invention. The head-separated camera 1 is configured such that a camera head 2 and a CCU 9 that controls the camera head 2 are connected by a camera cable 15.

  In the camera head 2, an optical image of a subject incident through a lens (not shown) is formed on a light receiving surface of an image sensor 3 made of, for example, a CMOS sensor. The image sensor 3 converts the optical image formed on the light receiving surface into a video signal corresponding to the optical image and outputs the video signal to the LVDS conversion driver 4.

  The LVDS conversion driver 4 serializes the digital video signal output from the image sensor 3 to convert it into an LVDS signal, and outputs it to the CCU 9 via the camera cable 15.

  The LVDS control unit 5 adjusts the amplitude voltage of the LVDS signal waveform and reinforces the rising (falling) part when the LVDS conversion driver 4 generates the LVDS signal. The LVDS signal is transmitted with a small signal amplitude in order to realize high-speed digital transmission. However, the voltage drop due to the internal resistance of the cable 15 further reduces the amplitude voltage of the differential signal, and the high frequency component of the video data due to the frequency characteristics Since the data rises, that is, the rise (fall) time of the data becomes long, the amplitude voltage adjustment of the signal waveform and the rise (fall) portion are strengthened in consideration of the influence of the cable 15. The type and size of adjustment are determined by the correction value 17 transmitted from the correction control unit 6.

  The correction control unit 6 calculates a voltage drop and outputs a correction value 17 of the LVDS signal supplied to the LVDS control unit 5. The correction control unit 6 stores a voltage measurement unit 7 that measures the voltage value of the DC voltage transmitted from the CCU 9, and a storage unit 8 that stores a correction value 17 set in advance based on the magnitude of the voltage effect and the reproduction state in the CCU 9. It has.

  The voltage measuring unit 7 measures the voltage value of the DC voltage transmitted from the CCU 9, and calculates a voltage drop value from a predetermined voltage value based on the measured voltage value. The storage means 8 is a ROM (Read Only Memory) or a flash memory, and stores a table 18 of LVDS signal correction values 17 supplied to the LVDS control unit 5. The correction control unit 6 extracts the correction value 17 from the table 18 based on the voltage drop value and supplies it to the LVDS control unit 5.

  The LVDS receiver 10 of the CCU 9 receives the LVDS signal transmitted from the LVDS conversion driver 4 of the camera head 2, deserializes the differential serial signal, and transmits the signal to the signal processing unit 11.

  The signal processing unit 11 performs various predetermined signal processing set in advance based on the control signal from the control unit 14, and transmits the generated video signal to the output circuit 12. The output circuit 12 outputs a video signal to a display device or the like.

  The control unit 14 includes an MPU (micro processing unit), and controls the LVDS receiver 10, the signal processing unit 11, and the output circuit 12 connected via the bus 13. The control unit 14 transmits a predetermined voltage to the correction control unit 6 of the camera head 2. The control unit 14 monitors whether the LVDS receiver 10 accurately latches the LVDS signal transmitted from the camera head 2 and monitors whether the video signal is accurately reproduced.

  FIG. 2 is a diagram showing an example of an eye mask of an LVDS signal waveform in a state received by the LVDS receiver 10. When the voltage drop due to the influence of the cable 15 increases, the amplitude of the differential signal decreases, and a phenomenon occurs in which the differential signal rise time and fall time become long. Whether the reproduction condition of the video signal in the CCU 9 is satisfied can be determined by the eye mask 16 of 1 UI (Unit Interval) of the LVDS signal. If a waveform is applied to this area, information cannot be accurately latched and erroneous data may be reproduced.

  As shown in FIG. 2, when the LVDS signal is applied to the eye mask 16 having a predetermined size indicated by the amplitude voltage A1 and the time T1, the video information may not be reproduced. Therefore, stable reproduction is possible if the eye mask 16 in the LVDS receiver 10 is always larger than the eye mask 16 having a predetermined size indicated by the amplitude voltage A1 and time T1.

  There is a correlation between the magnitude of the voltage drop due to the internal resistance of the cable 15 and the frequency characteristics, and as the cable length increases, the amplitude voltage of the differential signal decreases, and the high frequency component of the data attenuates due to the frequency characteristics. The rise (fall) time becomes longer, and the waveform enters the eye mask 16. At the manufacturing stage of the camera head 2 and the CCU 9 at the factory, the quality of the data reproduction state by the cable length can be known by investigating the relationship between the magnitude of the voltage drop due to the cable length and the reproduction state.

  When the voltage drop becomes large and the data reproduction state deteriorates, the LVDS receiver 10 can adjust the amplitude voltage of the signal waveform and strengthen the rising (falling) portion when the LVDS conversion driver 4 generates the LVDS signal. When received, it can be brought closer to a signal that is not affected by the voltage drop.

  FIG. 3 is a diagram illustrating an example of a waveform in a state where correction is added to the LVDS waveform output from the LVDS conversion driver 4. The waveform indicated by the alternate long and short dash line is the waveform before correction. By applying rising (falling) correction, it is possible to prevent the waveform from entering the eye mask.

  If the cable length is so short that no correction is necessary, these corrections should not be added. Adding the rise correction causes an undershoot in the latter half of the rise correction, which causes the waveform to be disturbed. Further, the correction increases the power consumption of the LVDS conversion driver 4, and there is a concern about the influence of heat generation. It is necessary to add an appropriate correction value according to the cable length.

  FIG. 4 is a diagram illustrating an example of the table 18 of the relationship between the voltage drop and the correction value. As for the magnitude of the voltage drop, when the control unit 14 of the CCU 9 transmits a predetermined voltage, for example, Va to the correction control unit 6 of the camera head 2, and the voltage at the voltage measurement unit 7 is Vb, the voltage drop Vc is , Vc = Va−Vb. The length of the cable 15 is changed, the magnitude of the voltage drop and the reproduction condition are measured, the correction value having a waveform that can be accurately reproduced is found, and the table 18 as shown in FIG. 4 can be created. In the table 18, n amplitude correction values and n rising correction values correspond to n voltage drop values from V1 to Vn, respectively. Information in the table 18 is stored in the storage means 8 of the correction control unit 6 at the manufacturing stage.

  FIG. 5 is a flowchart showing an example of the operation of the camera head separation type camera apparatus 1. When the user actually uses the camera head separation type camera device 1, a cable having an arbitrary length is used, and the camera head 2 and the CCU 9 are connected.

  In S <b> 11, after the power of the CCU 9 is turned on, the control unit 14 of the CCU 9 transmits a predetermined voltage to the correction control unit 6 of the camera head 2. In S12, the voltage measuring unit 7 measures the voltage value. In S13, the voltage measurement unit 7 calculates the magnitude of the voltage drop from the predetermined voltage value based on the measured voltage value.

  In S14, the correction control unit 6 extracts the correction value 17 from the table 18 of the storage unit 8 based on the magnitude of the voltage drop. The correction value 17 includes an amplitude correction value and a rising (falling) correction value. In the table 18 shown in FIG. 4, for example, when the voltage drop value is V1 or more and less than V2, A1 is extracted as the amplitude correction value, and E1 is extracted as the rising correction value.

  In S <b> 15, the correction control unit 6 transmits the extracted correction value 17 to the LVDS control unit 5. In S <b> 16, the LVDS control unit 5 adjusts the amplitude voltage of the LVDS signal waveform and strengthens the rising (falling) part when the LVDS conversion driver 4 generates the LVDS signal based on the correction value 17.

  In S <b> 17, the LVDS conversion driver 4 serializes the digital video signal transmitted from the image sensor 3 based on the control signal of the LVDS control unit 5 to generate an LVDS signal. In S <b> 18, the LVDS conversion driver 4 outputs the generated LVDS signal to the CCU 9 via the camera cable 15. In S19, the LVDS receiver 10 of the CCU 9 receives the LVDS signal.

  As described above, the voltage measurement unit 7 measures the voltage drop caused by the cable 15, and the correction control unit 6 extracts the correction value 17 from the table 18 indicating the relationship between the voltage drop and the correction value stored in advance. Based on this, the LVDS control unit 5 adjusts the LVDS signal waveform, and the LVDS conversion driver 4 generates and transmits the waveform of the LVDS signal, so that an accurate video signal can be reproduced in the CCU 9.

  FIG. 6 is a block diagram illustrating a configuration of the camera head separation type camera apparatus 20 according to the second embodiment. Regarding the respective parts of the second embodiment, the same parts as those of the camera head separation type camera apparatus of the first embodiment shown in FIG. The second embodiment is different from the first embodiment in that the camera head 21 does not measure a voltage drop, and the CCU 24 includes a voltage measuring unit 26 that measures the voltage value of the DC voltage transmitted from the camera head 21. It is in.

  After the power of the CCU 24 is turned on, the control unit 25 of the CCU 24 supplies a predetermined voltage to the correction control unit 22 of the camera head 21. The correction control unit 22 transmits the voltage value supplied from the CCU 24 to the control unit 25 without changing the voltage value. The voltage measuring unit 26 in the control unit 25 measures the voltage value and calculates the voltage drop value. Therefore, the magnitude of the voltage drop corresponds to the voltage drop when the cable 15 is reciprocated. The control unit 25 transmits the voltage drop value to the correction control unit 22.

  The correction control unit 22 extracts the correction value 27 from the table 28 of the storage unit 23 based on the magnitude of the voltage drop transmitted from the control unit 25. The correction value 27 includes an amplitude correction value and a rising correction value.

  FIG. 7 is a diagram illustrating an example of the table 28 of the relationship between the voltage drop and the correction value according to the second embodiment. The magnitude of the voltage drop is transmitted from the control unit 25 of the CCU 24 to a predetermined voltage, for example, Ve, to the correction control unit 22 of the camera head 21, and further transmitted from the correction control unit 22 to the control unit 25. When the voltage is Vf, the voltage drop Vg can be obtained by Vg = Ve−Vf. By examining the relationship between the voltage drop value and the frequency characteristics by changing the length of the cable 15, a correspondence table between the cable length and the reproducible correction value as shown in FIG. 7 can be created. In the table 28, n amplitude correction values and n rising correction values correspond to n voltage drop values from Vs1 to Vsn, respectively. Information in the table 28 is stored in the storage means 23 of the correction control unit 22 at the manufacturing stage.

  In the table 28 shown in FIG. 7, for example, when the voltage drop value is Vs1, the amplitude correction value is As1 and the rising correction value is Es1. The correction control unit 22 transmits the extracted correction value 27 to the LVDS control unit 5.

  As described above, the voltage measuring unit 26 measures the voltage drop caused by the cable 15 when it is transmitted from the CCU 24 to the camera head 21 and further transmitted from the camera head 21 to the CCU 24, and the value of the voltage drop is corrected and controlled. 22, the correction control unit 22 extracts the correction value 27 from the table 28 indicating the relationship between the voltage drop and the correction value stored in advance, and the LVDS control unit 5 adjusts the LVDS signal waveform based on the correction value 27. When the LVDS conversion driver 4 generates and transmits the waveform of the LVDS signal, the CCU 24 can reproduce an accurate video signal.

  FIG. 8 is a block diagram illustrating a configuration of a camera head separation type camera apparatus 30 according to the third embodiment. Regarding the respective parts of the third embodiment, the same parts as those of the camera head separation type camera apparatus of the first embodiment shown in FIG. The third embodiment is different from the first embodiment in that the camera head 31 does not measure a voltage drop, and the camera head 31 is provided with a switch 34 for switching a correction value. The user can select a correction value according to the length of the cable 37.

  The correction control unit 32 outputs a correction value 38 set by the switch 34. The correction control unit 32 includes storage means 33 that stores a correction value 38 set in advance based on the reproduction state in the CCU 9. The storage unit 8 is a ROM (Read Only Memory) or a flash memory, and stores a table 39 of correction values 38 of LVDS signals supplied to the LVDS control unit 5. The correction control unit 32 extracts the correction value 38 set by the switch 34 from the table 39 and supplies it to the LVDS control unit 5.

  The control unit 36 of the CCU 35 includes an MPU and controls the LVDS receiver 10, the signal processing unit 11, and the output circuit 12 connected via the bus 13. The control unit 14 monitors whether the LVDS receiver 10 accurately latches the LVDS signal transmitted from the camera head 31, and monitors whether the video signal is accurately reproduced.

  FIG. 9 is an overview of the camera head separation type camera apparatus 30 according to the third embodiment. A switch 34 is provided in the housing of the camera head 31. The correction value 38 can be selected by the user operating the switch 34.

  FIG. 10 is a diagram illustrating an example of a table of the relationship between the switch setting value and the correction value according to the third embodiment. By changing the length of the cable 37, the relationship between the cable length and the reproduction state can be investigated, and a table 39 showing the relationship between the switch setting value and the correction value can be created. In the table 39, n amplitude correction values and n rising correction values correspond to n set values from SW1 to SWn, respectively. Information of the table 39 is stored in the storage means 33 of the correction control unit 32 at the manufacturing stage.

  In the table 39 shown in FIG. 10, for example, when the set value of the switch is SW1, the amplitude correction value is Asw1, and the rising correction value is Esw1. The correction control unit 32 transmits the extracted correction value 38 to the LVDS control unit 5.

  As described above, the correction value 38 is extracted from the table 39 indicating the relationship between the setting value of the switch 34 and the correction value 38 stored in advance by the correction control unit 32, and the LVDS control unit 5 outputs the LVDS signal based on the correction value 38. By adjusting the waveform and the LVDS conversion driver 4 generates and transmits the waveform of the LVDS signal, the CCU 35 can reproduce an accurate video signal.

  FIG. 11 is a block diagram illustrating a configuration of a camera head separation type camera apparatus 40 according to the fourth embodiment. In each part of the fourth embodiment, the same parts as those of the camera head separation type camera apparatus of the third embodiment shown in FIG. The fourth embodiment is different from the third embodiment in that the camera head 41 does not have a switch for switching the correction value, the CCU 44 is provided with a switch 46, and the control unit 45 determines the setting value of the switch 46. Is transmitted to the correction control unit 42. The user can select a correction value according to the length of the cable 48.

  A video signal is sent from the output circuit 12 of the CCU 44 to the display device 47, and the setting value of the switch 46 can be set while being displayed on the screen of the display device 47 by an OSD (On Screen Display) menu. The display device 47 may be inside the casing of the CCU 44 or may be an external casing different from the casing of the CCU 44.

  The control unit 45 of the CCU 44 includes an MPU, and controls the LVDS receiver 10, the signal processing unit 11, and the output circuit 12 connected via the bus 13. The control unit 45 monitors whether or not the LVDS receiver 10 accurately latches the LVDS signal transmitted from the camera head 41 and monitors whether or not the video signal is accurately reproduced. The control unit 45 transmits the value set by the switch 46 to the correction control unit 42 of the camera head 41 via the cable 48.

  The correction control unit 42 outputs a correction value 49 according to the set value of the switch 46 transmitted from the control unit 45. The correction control unit 42 includes storage means 43 that stores a correction value 49 that is set in advance based on the reproduction state in the CCU 44. The storage means 43 is a ROM (Read Only Memory) or a flash memory, and stores a table 50 of correction values 49 of LVDS signals supplied to the LVDS control unit 5. The correction control unit 42 extracts the correction value 49 from the table 50 and supplies it to the LVDS control unit 5.

  FIG. 12 is a diagram illustrating an example of a table 50 of the relationship between switch setting values and correction values according to the fourth embodiment. By changing the length of the cable 48, the relationship between the cable length and the reproduction state is investigated, and a table 50 showing the relationship between the switch setting value and the correction value can be created. In the table 50, n amplitude correction values and n rising correction values correspond to n setting values from SWc1 to SWcn, respectively. Information of the table 50 is stored in the storage means 43 of the correction control unit 42 at the manufacturing stage.

  In the table 50 shown in FIG. 12, for example, when the setting value of the switch is SWc1, the amplitude correction value is Aswc1, and the rising correction value is Eswc1. The correction control unit 42 transmits the extracted correction value 49 to the LVDS control unit 5.

  As described above, the correction control unit 42 receives the value set by the switch 46 of the CCU 44 from the control unit 45, and the table 50 showing the relationship between the setting value of the switch 46 and the correction value 49 stored in advance by the correction control unit 42. Then, the LVDS control unit 5 adjusts the LVDS signal waveform based on the correction value 49, and the LVDS conversion driver 4 generates and transmits the waveform of the LVDS signal. A video signal can be reproduced.

  In the block diagram showing the configuration of the camera head separated camera device 40 shown in FIG. 11, the control unit 45 monitors whether the LVDS receiver 10 accurately latches the LVDS signal transmitted from the camera head 41, and Whether the video signal is correctly reproduced is monitored, but when the LVDS receiver 10 cannot latch the LVDS signal or the video signal cannot be accurately reproduced, the control unit 45 restarts the camera head 41. To do.

  The control unit 45 changes the value of the correction value 49 when the camera head 41 is restarted. For example, in the table 50 shown in FIG. 12, the setting value is SWc1, the amplitude correction value is Aswc1, the rising correction value is Eswc1, the setting value is SWc2, the amplitude correction value is Aswc2, the rising correction value is Eswc2, and the correction value is large. Change to be. The control unit 45 repeats the restart until the LVDS receiver 10 can accurately latch the LVDS signal transmitted from the camera head 41 or until the video signal is accurately reproduced. By doing so, an accurate video signal can be reproduced in the CCU 44.

  Note that the present invention is not limited to the above-described embodiments as they are, and can be embodied by modifying the components without departing from the scope of the invention in the implementation stage. In addition, various inventions can be formed by appropriately combining a plurality of constituent elements disclosed in the embodiment. For example, some components may be deleted from all the components shown in the embodiment. Furthermore, constituent elements over different embodiments may be appropriately combined.

DESCRIPTION OF SYMBOLS 1 Camera head separation type camera apparatus 2 Camera head 3 Image pick-up element 4 LVDS conversion driver 5 LVDS control part 6 Correction control part 7 Voltage measurement part 8 Memory | storage means 9 CCU
DESCRIPTION OF SYMBOLS 10 LVDS receiver 11 Signal processing part 12 Output circuit 13 Bus 14 Control part 15 Cable 16 Eye mask 17 Correction value 18 Table 20 Camera head separation type camera apparatus 21 Camera head 22 Correction control part 23 Memory | storage means 24 CCU
25 Control unit 26 Voltage measurement unit 27 Correction value 28 Table 30 Camera head separation type camera device 31 Camera head 32 Correction control unit 33 Storage means 34 Switch 35 CCU
36 Control unit 37 Cable 38 Correction value 39 Table 40 Camera head separation type camera device 41 Camera head 42 Correction control unit 43 Storage means 44 CCU
45 Control unit 46 Switch 47 Display device 48 Cable 49 Correction value 50 Table

Claims (10)

In a camera head separation type camera device in which the camera head and camera control unit are connected by a cable,
The camera control unit measures a voltage drop of the DC voltage transmitted by the correction control unit without any change, and a control unit that transmits a predetermined direct current (DC) voltage to the correction control unit of the camera head. A voltage measuring unit,
The camera head generates an amplitude correction value and a rise correction value based on an LVDS conversion driver that transmits an LVDS signal to be transmitted to the camera control unit and a voltage drop value of a DC voltage measured by the voltage measurement unit. A camera head separation type camera apparatus comprising: the correction control unit; and an LVDS control unit that controls the LVDS conversion driver unit by using an amplitude correction value and a rising correction value generated by the correction control unit.   The correction control unit includes storage means for storing the magnitude of the voltage drop transmitted without modification by the correction control unit and the amplitude correction value and the rising correction value of the LVDS signal supplied to the LVDS control unit. 2. The camera head separation type camera apparatus according to claim 1, wherein the camera head is separated. In a camera head separation type camera device in which the camera head and camera control unit are connected by a cable,
The camera head or the camera control unit includes a switch for switching between an amplitude correction value and a rise correction value,
The camera head includes an LVDS conversion driver unit that transmits an LVDS signal to be transmitted to a correction control unit of the camera control unit, a correction control unit that switches and outputs an amplitude correction value and a rising correction value based on selection by the switch, An LVDS control unit that controls the LVDS conversion driver unit based on an amplitude correction value and a rising correction value switched by the correction control unit.   4. The camera according to claim 3, wherein the correction control unit includes storage means for storing an amplitude correction value and a rising correction value that are set in advance based on the cable length and a reproduction state in the camera control unit. Head separation type camera device. 4. The camera head separation type camera device according to claim 3, wherein the camera head includes the switch. 4. The camera head separation type camera apparatus according to claim 3, wherein the camera control unit includes the switch.   4. The camera head separation type camera device according to claim 3, wherein the camera control unit includes an output circuit for displaying information on the amplitude correction value and the rise correction value on an external display device. A control method in a camera head separation type camera device in which a camera head and a camera control unit are connected by a cable,
The camera control unit transmitting a predetermined DC (Direct Current) voltage to the correction control unit of the camera head;
An LVDS conversion driver of the camera head transmits an LVDS signal to the camera control unit;
The correction control unit generates the amplitude correction value and the rising correction value based on the voltage drop value of the DC voltage measured by the voltage measurement unit, which is transmitted by the correction control unit without modification;
An LVDS control unit controlling the LVDS conversion driver unit;
A control method for a camera head separation type camera device, comprising: In a camera head separation type camera device in which the camera head and camera control unit are connected by a cable,
The camera control unit includes control means for transmitting a predetermined DC (Direct Current) voltage to the correction control unit of the camera head,
The camera head includes an LVDS conversion driver that transmits an LVDS signal to be transmitted to the camera control unit, and a voltage measurement unit that is included in the correction control unit and measures a voltage drop of the DC voltage transmitted to the correction control unit. A correction control unit that generates an amplitude correction value and a rise correction value based on a voltage drop value of the DC voltage measured by the voltage measurement unit, and an amplitude correction value and a rise correction generated by the correction control unit. And a LVDS control unit that controls the LVDS conversion driver unit according to a value.   10. The camera head according to claim 9, wherein the correction control unit includes storage means for storing the magnitude of the voltage drop and an amplitude correction value and a rising correction value of an LVDS signal supplied to the LVDS control unit. Separable camera device.

Images