JP3790909B2 - Endoscope light source device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an endoscope light source device that turns on an emergency lamp when a main lamp used in endoscopy is turned off.
[0002]
[Prior art]
Conventionally, when an endoscope is used, a main lamp (hereinafter referred to as a main lamp) is used to perform endoscopic observation and treatment. However, when the operator cannot take his hands off, the main lamp is When it disappeared, it was possible to continue the endoscopic observation or treatment without taking your hands off the endoscope by switching to the emergency light as a spare light source.
[0003]
For this reason, the lamp-related unit of the endoscope light source device is a main lamp, an emergency light, a power supply for the main lamp, a power supply for the emergency light, It consisted of a control circuit for switching to the lamp.
[0004]
For example, in Japanese Patent Application No. 58-135540, a driving power source is provided for each of a discharge lamp as a main light source, an ignition circuit for an electric lamp as an auxiliary light source, and an auxiliary light source lighting circuit for an electric light as an auxiliary light source. If the main light source is turned off, and the main light source is turned off, the auxiliary light source is turned on.
[0005]
As a result, even if the endoscope operator cannot be released during use, even if the main light source is turned off for some reason, it automatically switches to the auxiliary light. I could continue to operate the endoscope without releasing it.
[0006]
[Problems to be solved by the invention]
However, because the main lamp, the emergency light, the main lamp power supply, the emergency light power supply, and the control circuit for detecting that the main lamp was broken and switching to the emergency light were configured separately, This was accompanied by an increase in the size of the light source device, an increase in cost, and an increase in the number of study steps.
[0007]
Conventionally, for example, as in Japanese Patent Application No. 58-135540, a driving power source is provided for each light source, such as an ignition circuit for a discharge lamp as a main light source and an auxiliary light source lighting circuit for a lamp as an auxiliary light source. It was. For this reason, there are problems that the light source device is enlarged, the cost is increased, and the number of examination steps is increased.
[0008]
The present invention has been made in view of the above points, and provides a light source device for an endoscope that can share a power source for lighting a main lamp and an emergency light, and can be reduced in size, cost, and man-hours to be studied. The purpose is to do.
[0009]
[Means for Solving the Problems]
An endoscope light source device according to the present invention includes a first light source for generating illumination light that illuminates a subject via an endoscope, a second light source having a driving power different from that of the first light source, A single light source power source that can apply a lighting output to the first light source and can apply a lighting output to the second light source, and an output of the light source power source to the first light source. A light source output power switching means for switching between the light source and the second light source for output, and detecting the output of the light source power source to determine whether or not the first light source is disconnected When the disconnection determining means and the disconnection determining means determine that the first light source is in a disconnected state, the light source output power switching means is controlled to output the power from the light source power source. Switch from one light source to the second light source and And control means for controlling so as to applied power to the second light source, characterized by comprising a.
[0010]
As a method of switching the power, for example, a method of changing the lamp voltage by changing the switching frequency of the switching circuit is conceivable. This utilizes the fact that the output voltage increases when the switching frequency is increased, and the output voltage decreases when the switching frequency is decreased.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings.
(First embodiment)
FIG. 1 shows the configuration of an endoscope light source device according to a first embodiment of the present invention. In this embodiment, a main lamp as a first light source (lamp) used as an illumination light source for normal observation and an emergency use as a second light source used for emergency when the main lamp does not light up An embodiment in which the same type of lamp is used and in particular a discharge tube type lamp such as a metal halide lamp or a xenon lamp is used will be described.
[0012]
In the endoscope light source device 1 of the first embodiment shown in FIG. 1, the commercial power source 2 is connected to the input terminal of the switching circuit 3 that forms a common lamp lighting means, and is supplied with AC power from the commercial power source 2. On the other hand, the rectification circuit (not shown) in the switching circuit 3 converts the current into a direct current, further switches a switching element such as a switching transistor, and outputs it to the primary circuit of the transformer 4 connected to the output terminal of the switching circuit 3. 4 generates a lamp voltage for lighting the lamp.
[0013]
The secondary circuit of the transformer 4 is connected to a starter 5 that generates a high voltage for starting the lamp operation and a lamp switching circuit 6 that switches the lamp, which is necessary in the case of a discharge tube type lamp. 6, one of the main lamp 7 and the emergency lamp 8 is selectively connected.
[0014]
The secondary circuit of the transformer 4 is connected to one input terminal of the comparator 9, and the reference voltage generated by the reference voltage setting means 10 is applied to the other input terminal of the comparator 9. A difference voltage obtained by comparing the two voltages is output as an output signal to a pulse width modulation circuit (hereinafter abbreviated as PWM) 11. Specifically, an error voltage corresponding to the deviation amount of the lamp voltage with respect to the reference voltage is output to the PWM 11.
[0015]
In the configuration shown in FIG. 1, an AC voltage is generated in the secondary circuit of the transformer 4. Therefore, when the reference voltage is a DC voltage, the output for comparison is a pulsating flow. The driving of the PWM 11 may be controlled by this pulsating flow, or the driving of the PWM 11 may be controlled by an average value of the pulsating flow. Alternatively, the voltage may be applied from the secondary circuit of the transformer 4 to the comparator 9 via a rectifier (and a smoothing circuit). In the following description, for simplification, the input and output to the comparator 9 will be described as averaged (ie, DC level).
[0016]
The PWM 11 outputs a pulse signal having a pulse width corresponding to the value of the input signal to the switching circuit 3, and the switching circuit 3 changes the switching frequency according to the pulse signal and outputs it to the transformer 4. Is converted to a voltage corresponding to the switching frequency on the secondary circuit side. Then, feedback control is performed so that the average value of the lamp voltage of the secondary circuit of the transformer 4 becomes the reference voltage.
[0017]
Further, the output signal of the comparator 9 is input to the extinction detection means 12 that detects the extinction of the main lamp 7, and the extinction detection signal output from the extinction detection circuit 12 is input to the reference voltage setting means 10 and the lamp switching circuit 6. By this signal, the reference voltage setting means 10 is controlled to change the reference voltage, and the lamp switching circuit 6 is controlled to switch the lamp (to which the lamp voltage is supplied).
[0018]
That is, the output signal of the comparator 9 is almost close to 0 in a normal state by feedback control. In this state, the output of the light extinguishing detection means 12 is a signal level (for example, “L”) that does not detect the light extinction. When the output signal of the comparator 9 changes significantly, the extinguishing detection circuit 12 judges that the main lamp 7 is extinguished such as out of lamp, and the signal level (eg, “H”) at which extinction is detected is extinguished. A detection signal is output. The reference voltage setting means 10 is controlled to switch the reference voltage so that a reference voltage suitable for lighting the emergency lamp 8 is output, and the lamp switching circuit 6 is changed to the emergency lamp 8. Switch so that the lamp voltage is supplied.
[0019]
Specifically, for the lamp switching circuit 6, two common contacts C 1 and C 2, which are normally connected to the contacts A 1 and A 2 connected to the main lamp 7, are connected to the emergency lamp 8. It switches so that it may conduct with B1 and B2.
[0020]
Further, when it is determined that the extinguishing detection unit 12 is in the extinguishing state, a signal is sent to the starter 5 through a control line (not shown), and control for newly starting a high-pressure lighting operation for starting the emergency lamp 8 is performed. .
[0021]
In addition, the light by lighting of the main lamp 7 etc. is supplied to the end part of the light guide of the endoscope (not shown), and the light transmitted by the light guide is the front end of the light guide attached to the illumination window of the endoscope front end part. It is emitted from the surface to the subject side such as an affected part in the body cavity and becomes illumination light for illuminating the subject side.
[0022]
The illuminated subject is imaged through an objective lens system attached to an observation window disposed adjacent to the illumination window, and can be observed with the naked eye through an image guide or with a monitor through a solid-state image sensor. become.
[0023]
Unlike the power suitable for lighting the main lamp 7 and the power suitable for lighting the emergency lamp 8, in the present embodiment, in order to be able to supply power suitable for lighting each lamp, The reference voltage setting means 10 controls the average value of the lamp voltage applied to the lamp to a value (reference voltage) corresponding to the power suitable for lighting the lamp.
[0024]
In the present embodiment, a common lighting means capable of selectively lighting the main lamp 7 and the emergency lamp 8, a detection means for detecting the extinction state of the main lamp 7, and the main lamp based on the output of the detection means. Switching means for selectively connecting one of the emergency lamp 8 and the emergency lamp 8 to the lighting means, and power suitable for lighting the main lamp 7 or the emergency lamp 8 connected to the lighting means based on the output of the detection means It is characterized in that it is provided with power reference value setting means for supplying.
[0025]
Next, the operation of this embodiment will be described.
When a power switch (not shown) is turned on, electric power from the commercial power source 2 is supplied to the switching circuit 3, and a lamp voltage is generated in the secondary circuit of the transformer 4 through the switching circuit 3. In the initial state when the power is turned on, the extinguishing detection means 12 maintains a state where no extinguishing is detected. Specifically, the output signal level of the turn-off detection means 12 is “L”.
[0026]
In this state, as shown in FIG. 1, the lamp switching circuit 6 is in a state where the common contacts C1 and C2 are electrically connected to the contacts A1 and A2, and the lamp voltage is supplied to the main lamp 7 via the starter 5.
[0027]
Further, in this initial state, the extinction detection means 12 controls the reference voltage setting means 10 to output a reference voltage suitable for turning on the main lamp 7. Further, the extinguishing detection means 12 controls the starter 5 to start the lighting operation, the high voltage is applied to the main lamp 7 for a short time, the lighting operation starts, and then the lighting state is maintained by the lamp voltage.
[0028]
This lamp voltage is compared with the reference voltage from the reference voltage setting means 10 by the comparator 9, and the comparison result is fed back to the switching circuit 3 again via the PWM 11, so that the average value of the lamp voltage is always set to the reference voltage. The value of the lamp voltage is controlled to be a value that matches the reference voltage of the means 10.
[0029]
For example, when the average value of the lamp voltage is higher than the reference voltage, the comparator 9 applies an output signal having a negative polarity to the pulse width control terminal of the PWM 11, and the PWM 11 in this case is a pulse that makes the pulse width smaller. The signal is output to the switching circuit 3. In the case of a pulse signal having a smaller pulse width, the switching circuit 3 performs an operation of lowering the switching frequency, so that the lamp voltage of the secondary circuit of the transformer 4 is lowered to a lamp voltage lower than that in the previous state. Therefore, the value becomes closer to the reference voltage, and the state almost matches the reference voltage by repeating such feedback.
[0030]
Conversely, when the lamp voltage is lower than the reference voltage, the comparator 9 applies a positive polarity output signal to the pulse width control end of the PWM 11, and the PWM 11 in this case outputs a pulse signal having a larger pulse width. Output to the switching circuit 3. In the case of a pulse signal having a larger pulse width, the switching circuit 3 performs an operation of increasing the switching frequency, whereby the lamp voltage of the secondary circuit of the transformer 4 is increased, and the lamp voltage becomes higher than that in the previous state. Therefore, the value becomes closer to the reference voltage, and the state almost matches the reference voltage by repeating such feedback.
[0031]
By turning on the main lamp 7 in this state (normal operation state), the light is used as illumination light for endoscopic observation, so that normal endoscopic observation can be performed.
[0032]
After the time necessary to reach the normal operation state, the light extinguishing detection means 12 performs the operation for detecting the extinction. When the main lamp 7 is extinguished for some reason, such as the life of the main lamp 7 or manufacturing variations, during this normal operation state, the extinguishing detection means 12 causes a significant change in the output of the comparator 9 at that time. If detected, it is determined that the main lamp 7 is extinguished, and an extinction detection signal is output.
[0033]
For example, if the electrode of the main lamp 7 is disconnected and no current flows, the lamp voltage becomes significantly higher than the reference voltage from the reference voltage setting means 10, and the output of the comparator 9 changes significantly. When the output of the comparator 9 changes significantly, the turn-off detection means 12 determines that the main lamp 7 has been turned off, and turns off the detection to notify the reference voltage setting means 10 and the lamp switching circuit 6 that the main lamp 7 has been cut off. Output a signal.
[0034]
The reference voltage setting means 10 generates a reference voltage that is suitable for lighting the emergency lamp 8, and the lamp switching circuit 6 performs switching so that the lamp voltage is applied to the emergency lamp 8.
[0035]
Further, the extinguishing detection means 12 sends a signal for starting the lighting operation to the starter 5 to generate a high voltage for a short time to turn on the emergency lamp 8 and then maintain the lighting state by the lamp voltage. In this lighting state, the lamp voltage suitable for lighting the emergency lamp 8 is maintained by the reference voltage as described in the operation of the main lamp 7.
[0036]
With the above operation, even when the main lamp 7 is cut off for some reason during the endoscopic observation, the endoscopic observation can be continued by automatically switching to the emergency lamp 8.
[0037]
According to the present embodiment, since the common lighting means capable of selectively lighting the main lamp 7 and the emergency lamp 8 is provided, one of the two lighting means dedicated to the main lamp and the emergency lamp is provided. This eliminates the need to reduce the size and cost of the light source device, and to reduce the number of examination steps required for each lighting means.
[0038]
In addition, the emergency lamp 8 is connected to the common lighting means from the main lamp 7 by the output of the detection means for detecting the extinguishing state of the main lamp 7, and power suitable for lighting the emergency lamp 8 is supplied. Therefore, even if the main lamp 7 is cut off for some reason during endoscopic observation, the endoscopic observation can be continued without interruption by automatically switching to the emergency lamp 8. There is also an effect that can be.
[0039]
In the case where the illumination light quantity of the emergency lamp is considerably smaller than the illumination light quantity due to the lighting of the main lamp 7, and the endoscope is an electronic endoscope provided with a solid-state imaging element, the imaging period of the solid-state imaging element May be variably controlled (specifically, lengthened) so that a bright and good S / N image can be obtained as in the case of being imaged under illumination by the main lamp 7 (responsiveness is sacrifice).
[0040]
For example, under illumination with the main lamp 7, when one frame period as an imaging period for obtaining one color image is 1/30 seconds, for example, when switching to the emergency lamp 8, several times to The image capturing period may be extended up to about 10 times so that an easily identifiable image can be obtained.
[0041]
(Second Embodiment)
FIG. 2 shows a configuration of an endoscope light source device according to a second embodiment of the present invention. In this embodiment, the main lamp and the emergency lamp are different types. In particular, a discharge tube type lamp such as a metal halide lamp or a xenon lamp is used as the main lamp, and a filament type lamp such as a halogen lamp is used as the emergency lamp. It is a thing when used for.
[0042]
The endoscope light source device 21 of the second embodiment shown in FIG. 2 is the same as the endoscope light source device 1 of FIG. 1, but the lamp switching circuit 6 is provided in the secondary circuit of the transformer 4 and the common contact C1. , C2 is supplied with power to the main lamp 7 via the starter 5 when the contacts A1 and A2 are turned on, but without the starter 5 when the contacts C1 and C2 are turned on with the contacts B1 and B2. Electric power is supplied to the filament-type emergency lamp 22. Other configurations are the same as those of the endoscope light source device 1 of FIG.
[0043]
Next, the operation of this embodiment will be described.
[0044]
The operation of maintaining the lighting and lighting state of the main lamp 7 with the power switch ON is the same as in the first embodiment. Then, the turn-off detection means 12 performs a turn-off detection operation.
[0045]
However, during normal operation, when the main lamp 7 is extinguished for some reason, such as the life of the main lamp 7 or manufacturing variations, the lamp voltage changes and the output of the comparator 9 changes significantly. This significant change is detected by the extinguishing detection means 12, and it is determined that the main lamp 7 has been extinguished, and notifies the reference voltage setting means 10 and the lamp switching circuit 6 that the main lamp 7 has been cut off.
[0046]
The reference voltage setting means 10 generates a reference voltage that is suitable for lighting the emergency lamp 22, and the lamp switching circuit 6 performs switching so that the lamp voltage is applied to the emergency lamp 22. By this switching, the filament type emergency lamp 22 is turned on.
[0047]
The emergency lamp 22 is controlled so that the average value of the lamp voltage matches the reference voltage.
[0048]
With the above operation, even when the main lamp 7 is cut off for some reason during the endoscopic observation, the endoscopic observation can be continued by being automatically switched to the emergency lamp 22.
[0049]
In the present embodiment, the emergency lamp 22 is turned on immediately when the lamp switching circuit 6 is switched so that the emergency lamp 22 is turned on. Therefore, the emergency lamp 22 is suitable for lighting the emergency lamp 22. When the average value of the lamp voltage is smaller than the average value in the case of the main lamp 7, the reference voltage is switched before the lamp switching, or at least the reference voltage is not switched after the lamp switching. It is desirable to do so.
[0050]
If the switching order that does not satisfy this condition, that is, if the reference voltage is switched after the lamp is switched first, the lamp voltage is changed to an appropriate value after an excessive lamp voltage is applied to the emergency lamp 22. Therefore, there is a possibility that the emergency lamp 22 is damaged when an excessive lamp voltage is applied.
[0051]
In the present embodiment, even when the main lamp 7 and the emergency lamp are different types of lamps, a light source device having the same effect as the first embodiment can be realized.
[0058]
Note that the extinguishment detection means 12 for detecting the extinction of the main lamp 7 detects the extinction of the main lamp 7 by detecting a significant fluctuation in the output of the comparator 9. The extinction may be detected by detecting the value or the amount of change.
[0059]
That is, since the value of the current flowing through the main lamp 7 in a normal lighting state is substantially constant, if the current value is significantly different from the value, it is determined that the lamp is turned off and the emergency lamp 8 or 22 is turned on. Anyway.
Further, when it is detected that the main lamp 7 is turned off, the operator may be notified of the turn-off of the main lamp 7 by a buzzer sound or lighting of an LED or the like.
[0060]
[Appendix]
1. A first light source for generating illumination light that illuminates a subject via an endoscope;
A second light source different from the first light source;
A lighting device capable of selectively lighting the first light source and the second light source;
Detecting means for detecting that the first light source is no longer lit;
Switching means for switching lighting of the first or second light source based on a signal from the detection means;
A power reference value setting means for outputting power corresponding to the first or second light source based on a signal from the detection means;
An endoscope light source device characterized by comprising:
[0061]
2. A discharge tube as a main lamp that generates illumination light for illuminating a subject via an endoscope;
A discharge tube as an emergency lamp different from the discharge tube;
A switching power supply for lighting the two lamps;
Output setting means for determining the output power of the switching power supply;
A comparator for comparing the reference voltage setting means and the output of the switching power supply;
A control signal generator for generating a control signal for controlling the switching power supply from the output of the comparator;
Detection means for detecting the turn-off of the main lamp;
Lamp switching means for switching to a main lamp or an emergency lamp based on the signal from the detection means;
An endoscope light source device, wherein a reference voltage from the reference voltage setting means is changed based on a signal from the detection means.
[0062]
3. A discharge tube as a main lamp for illuminating a subject through an endoscope;
A filament-type light source as an emergency lamp different from the discharge tube;
A switching power supply for lighting the two lamps;
Output setting means for determining the output power of the switching power supply;
A comparator for comparing the reference voltage setting means and the output of the switching power supply; a control signal generator for generating a control signal for controlling the switching power supply from the output of the comparator;
Detection means for detecting the turn-off of the main lamp;
Lamp switching means for switching to a main lamp or an emergency lamp based on the signal from the detection means;
An endoscope light source device, wherein a reference voltage from the reference voltage setting means is changed based on a signal from the detection means.
[0063]
4). A discharge tube as a main lamp for illuminating a subject through an endoscope;
A filament type lamp as an emergency lamp different from the discharge tube;
A switching power supply for lighting the two lamps;
Output setting means for determining the output power of the switching power supply;
A comparator for comparing the reference voltage setting means and the output of the switching power supply;
A control signal generator for generating a control signal for controlling the switching power supply from the output of the comparator;
Detection means for detecting the turn-off of the main lamp;
Lamp switching means for switching to a main lamp or an emergency lamp based on the signal from the detection means;
An endoscope light source device comprising:
[0064]
【The invention's effect】
As described above, according to the present invention, since the lighting control of the first light source and the second light source can be performed with one lighting device, the size can be reduced as compared with the two dedicated lighting devices. Costs can be reduced, and the study time for each separate lighting device can be reduced.
[Brief description of the drawings]
FIG. 1 is a configuration diagram of an endoscope light source device according to a first embodiment of the present invention.
FIG. 2 is a configuration diagram of an endoscope light source device according to a second embodiment of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Endoscope light source device 2 ... Commercial power supply 3 ... Switching circuit 4 ... Transformer 5 ... Starter 6 ... Lamp switching circuit 7 ... Main lamp 8 ... Emergency lamp 9 ... Comparator 10 ... Reference voltage setting means 11 ... PWM
12 ... Light extinction detection means

Claims (1)

A first light source for generating illumination light that illuminates a subject via an endoscope;
A second light source having a driving power different from that of the first light source;
A single light source that can apply a lighting output to the first light source and can apply a lighting output to the second light source;
Light source output power switching means for switching and outputting the output of the light source power source to the first light source and the second light source;
Disconnection determining means for determining whether or not the first light source is in a disconnected state by detecting an output of the power source for the light source;
When the disconnection determining means determines that the first light source is in a disconnected state, the light source output power switching means is controlled to output the output from the light source from the first light source to the first light source. Control means for switching to two light sources and controlling to apply a preset power to the second light source;
An endoscope light source device characterized by comprising:

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