JPH0695995B2 - Electronic endoscopic device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Field of Industrial Application) The present invention relates to an electronic endoscope apparatus having a processing function for converting functional information into an image, and particularly to improvement of a control system for the processing function. .

(Prior Art) As is well known, in order to obtain a functional information image such as a hemoglobin distribution image, this type of electronic endoscope apparatus places each interference filter having a different central transmission wavelength on the light source optical path. The body cavity is photographed by an image sensor such as a CCD under each illumination that is sequentially inserted, and different monochromatic light images are obtained based on the output signal from the image sensor, and then the difference in absorbance between the two monochromatic light images is calculated. The functional information image obtained by the calculation is displayed on, for example, a monitor.

Then, when the above monochromatic light image is taken, the irradiation light amount is adjusted so that the luminance signal level in the output signal of the image pickup device is controlled to fall within a prescribed level range.

(Problems to be Solved by the Invention) However, even if the control for adjusting the irradiation light amount is performed as described above, the luminance signal level in the output signal of the image sensor is equal to or higher than the saturation level, or
May fall below the noise level. On the other hand, in the conventional system configuration of the electronic endoscope apparatus of this type, the arithmetic processing for obtaining the functional information is continuously executed regardless of the change of the output signal of the image sensor.

Therefore, in the conventional case, there is a problem that error information may be included in the function information image displayed on the monitor.

The present invention has been made in view of such circumstances, and an object thereof is to provide an output signal from an image pickup device when the irradiation light amount of a monochromatic light irradiation light source is a light amount suitable for obtaining a functional information image. An object of the present invention is to provide an electronic endoscope apparatus in which arithmetic processing for obtaining a functional information image is performed based on the above.

[Structure of Invention]

(Means for Solving the Problems) In order to achieve the above object, the present invention provides a hemoglobin amount of a subject or oxygen of hemoglobin on the basis of an output signal from an imaging device that captures an image of a subject under illumination by a monochromatic light source. Arithmetic processing means for executing arithmetic processing for obtaining image information relating to saturation, light quantity judging means for judging whether the luminance signal level in the output signal of the image pickup device is within a specified level range, and this light quantity judging means And a control means for setting a period during which it is determined that the value is out of the level range as a function stop period of the arithmetic processing means.

(Operation) With the configuration according to the present invention, when the luminance signal level in the output signal of the image pickup device is out of the specified level range, this is determined by the light amount determination means. Then, during the period when the light amount determination means determines that it is out of the specified level range, the control means sets the arithmetic processing means to the function stop period.

Therefore, the arithmetic processing for obtaining the functional information image is performed based on the output signal from the image pickup device when the irradiation light amount of the monochromatic light irradiation light source is a light amount suitable for obtaining the functional information image.

(Embodiment) FIG. 1 is a block diagram showing a configuration of an electronic endoscope apparatus of an embodiment to which the present invention is applied.

The electronic endoscope apparatus of this embodiment is provided with a CPU 1 as a control center of the entire system, and by this CPU 1, a light amount controller 2, a camera controller unit (hereinafter referred to as CCU) 3, an A / D converter 4 and a switching device. 5, normal optical frame memory 6, λ ₁ frame memory 7, λ ₂ frame memory 8,
λ ₃ frame memory 9, λ ₄ frame memory 10, arithmetic circuit
11, function image frame memory 12, display memory 1
3, D / A converter 14, light intensity judgment circuit 15, motor controller
16 and so on are controlled by a microprocessor.

Then, when the middle part of the endoscope scope 17 is introduced into the body cavity of the subject and the inside of the body cavity is imaged, the light amount controller 2
Xenon (Xe) lamp 18 and aperture controller 19
The motor controller 16 drives and controls the motor unit 20.

In addition, the rotary disk 21 of the motor unit 20 has a filter disc
22 is configured to be removable, and this filter disc 22
When obtaining the functional information corresponding to the hemoglobin amount and the oxygen saturation of hemoglobin, as shown in FIG. ₂ , the interference filters of λ ₁ , λ ₂ , λ ₃ and λ ₄ and the light amount attenuation filter indicated by ND This is a filter disc formed by arranging and.

In each of these units, the light amount controller 2 controls the current flowing through the Xe lamp 18 in accordance with the determination state of the light amount determination circuit light amount 15, while controlling the aperture of the diaphragm 23 to control the light source unit.
The amount of light emitted from 24 is automatically adjusted. In the light source unit 24, 25 is a condenser lens and 26 is a reflector.

The motor controller 16 removes the filter disc 22 from the optical path of the Xe lamp 18 during normal light photography, and when an operation for obtaining a functional information image is performed by the keyboard 27,
Place the filter disc 22 on the optical path of the Xe lamp 18 and
The motor unit 20 is driven and the filter disc 22 is rotated in order to sequentially switch the interference filters λ _{1 to} λ ₄ and repeatedly insert the filters into the optical path of the Xe lamp 18. When the filter disc 22 is rotated by such a motor controller 16, the light source 24 functions as a monochromatic light irradiation light source.

The light amount determination circuit 15 controls each interference filter λ ₁ under the control of the CPU 1 when the selection operation for obtaining the functional information image is performed.
The output signal of the CCU 3 that changes depending on the light receiving state of the solid-state image sensor (not shown) mounted at the distal end of the endoscope scope 17 in the middle of the path at each insertion period of sequentially inserting ~ λ ₄ into the optical path of the Xe lamp 18 When it is determined that most of the luminance signal levels are within the prescribed level range and it is determined that most of the luminance signal levels are outside the prescribed level range, this determination output is used as the light amount controller 2 and the arithmetic circuit 11 And send to CPU1.
It should be noted that during normal image capturing, a signal indicating a change in the luminance signal level in the output signal of the CCU 3 is sent to the light amount controller 2.

The CPU 1 itself sets the period in which the light intensity determination circuit 1 determines that the brightness signal level of the CCU 1 is out of the specified level range as the function stop period of the arithmetic circuit 11, and the light amount in the function stop period of the arithmetic circuit 11. Control to restart the controller 2 is performed. Then, when the light amount determination circuit 15 outputs a determination that the luminance signal level of the CCU 1 is within the specified level range by this control, the control for permitting the arithmetic processing of the arithmetic circuit 11 is performed. Further, in synchronization with the function stop period of the arithmetic circuit 15, on the screen of the display 28, a message area 28a as shown in FIG. 3 is displayed in order to display that the process of obtaining the function information image is interrupted. It controls the reading of the message memory 29, and as shown in FIG.
The process display LED 27b of 27 controls to display that the process for obtaining the function information is interrupted. In FIG. 4, the LED 27a indicates that images are collected in the memories 7 to 10 of λ ₁ to λ ₄ . 27c is a functional image switch.

The operation of the configuration as described above will be described. During normal observation, the filter disk 22 is driven by the motor unit 20.
Is removed from the optical path of the Xe lamp 18, and in this case CC
Since the signal indicating the luminance signal level in the output signal of U3 is applied from the light quantity determination circuit 15 to the light quantity controller 2, the light quantity controller 2 is kept in the ON state. Then, the electric signal obtained by imaging the inside of the body cavity with the endoscope 17 is converted into analog image data by the CCU 3, and A / D
It is digitized by the converter 4 and sequentially stored in the normal optical frame memory 6 through the switch 5. The image data sequentially stored in the normal optical frame memory 6 is sent to the display memory 13 under the read control of the CPU 1, and the image data once stored in the display memory 13 is analog image data by the D / A converter 14. Is converted into a display and sent to the display 28. Therefore, the display
An image of the normal shooting contents is displayed on 28.

When performing normal imaging in this way, it becomes necessary to measure the amount of hemoglobin and the oxygen saturation of hemoglobin, and when an input operation to that effect is performed with the keyboard 27, the filter disk 22 shifts and the Xe lamp 18 , The ND filter is inserted first, and then the ND filter is inserted in the order of λ ₁ → λ ₂ → λ ₃ → λ ₄ → ND → λ ₁ according to the rotational drive of the motor unit 20. become.

In synchronization with this, the switching device 5 sequentially selects the λ ₁ frame memory 7, the λ ₂ frame memory 8, the λ ₃ frame memory 9, the λ ₄ frame memory 10, and the normal light image memory 6 under the control of the CPU _1. shooting of each monochromatic light image to [lambda] ₄ is performed, to [lambda] ₄ frame memory 7 to 10 ₁ each of its monochromatic light image λ
Stored in each.

At this time, the light quantity determination circuit 15 determines whether most of the luminance signal levels in the output signal of the CCU 3 are within the specified level range. When most of the luminance signal levels are within the specified level range, when each monochromatic light image is stored in each of the frame memories 7 to 10 of λ _{1 to} λ ₄ ,
lambda _1, lambda _2, the calculation of oxygen saturation for each pixel of each single-color light image stored in the frame memory 7, 8, 9 of lambda ₃ is executed, followed by lambda _3, lambda ₄ of the frame memory 9, The calculation for obtaining the hemoglobin amount is executed for each pixel of each monochromatic light image stored in 10.

These respective calculation results are sent to the display memory 13 via the functional image frame memory 12. Therefore, the functional information image showing the oxygen saturation and the amount of hemoglobin is displayed on the display memory 27.

However, when most of the luminance signal level in the output signal of CCU3 is out of the specified level range, that is, when most of the luminance signal level is equal to or higher than the saturation level or is equal to or lower than the noise level, The arithmetic circuit 11 is disabled by the function of the CPU 1 as the processing condition setting means. At the same time, the light amount controller 2 is restarted to adjust the light amount of the light source unit 24, and as shown in FIG. 3, an interruption display of the process of obtaining the function information image is displayed in the message area 28a of the display 28, and in FIG. As shown, an interruption display is made on the keyboard 27. Each of these operations is performed until the luminance signal level in the output signal of the CCU 3 falls within the specified level range and the function stop of the arithmetic circuit 11 is released accordingly.

In this way, when most of the luminance signal levels in the output signal of the CCU 3 fall within the specified level range, the arithmetic circuit 11
Calculation processing is restarted, and the display 27
A functional information image showing the oxygen saturation and the amount of hemoglobin is displayed above.

As described above, in one embodiment of the present invention, when most of the luminance signal levels in the output signal of the CCU 3 are out of the specified level range, the monochromatic light image has each frame memory 10 of λ ₁ to λ _4. However, since the arithmetic circuit 11 stops functioning,
The function information image displayed on the display 28 does not include error information.

〔The invention's effect〕

As described above, the electronic endoscope apparatus of the present invention determines whether the irradiation light amount of the monochromatic light irradiation light source is suitable for obtaining the functional information image according to the change of the luminance signal level in the output signal of the image sensor. If the light amount determination means determines that the irradiation light amount is not appropriate, the control means stops the operation processing means, and then the light amount determination means makes the brightness signal level within the specified level range. When
The arithmetic processing of the arithmetic processing means is restarted.

Therefore, according to the present invention, it is possible to prevent the situation in which the function information image contains erroneous information, and the reliability of the function information image is remarkably improved. .

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of an endoscope apparatus of an embodiment to which the present invention is applied, FIG. 2 is a detailed explanatory view of a filter disc, and FIG. 3 is on a display in an embodiment of the present invention. FIG. 4 is a detailed view of the keyboard showing the display mode of FIG. 1 …… CPU 2 …… Light intensity controller 3 …… CPU 4 …… A / D converter 5 …… Switcher 6 …… Transmission frame memory 7 …… λ ₁ frame memory 8 …… λ ₂ frame memory 9 …… λ ₃ frame memory 10 …… λ ₄ frame memory 11 …… Arithmetic circuit 12 …… Functional image frame memory 13 …… Display memory 14 …… D / A converter 15 …… Light intensity judgment circuit 16 …… Motor controller 17 …… Endoscope scope 18 …… Xe lamp 19 …… Aperture controller 20 …… Motor unit 21 …… Rotating shaft 22 …… Filter disc 23 …… Aperture 24 …… Light source section 25 …… Condenser lens 26 …… Reflector 27 …… Keyboard 28 …… Display

Claims (3)

[Claims] 1. Arithmetic processing means for executing arithmetic processing for obtaining image information relating to the hemoglobin amount of a subject or the oxygen saturation level of hemoglobin based on an output signal from an image pickup device for capturing an image of a subject under illumination by a monochromatic light irradiation light source. A light amount determining means for determining whether or not a luminance signal level in an output signal of the image sensor is within a prescribed level range; and a period during which the light amount determining means determines that the luminance signal level is out of the prescribed level range. An electronic endoscope apparatus, comprising: a control unit that sets a function stop period of a processing unit. 2. The control means controls to restart the light quantity adjusting means of the monochromatic light irradiation light source during a period in which the arithmetic processing means stops functioning, and by this control, the light quantity judging means keeps the light quantity within a prescribed level range. 2. The electronic endoscope apparatus according to claim 1, wherein the arithmetic processing of the arithmetic processing unit is permitted after the determination is made. 3. The electronic endoscope according to claim 1, wherein the control means controls the display of the function stop on the display means in synchronization with the function stop period of the arithmetic processing means. Mirror device.