JPH0698118B2 - Endoscope device - Google Patents

Description

Description: [Object of the Invention] (Industrial field of application) [0001] The present invention relates to an endoscope apparatus that performs image acquisition by interlacing scanning of an imaging camera, and in particular, a processing mechanism for displaying a freeze image. Regarding the improvement of.

(Prior Art) Conventionally, as a CCD color camera used for an electronic endoscope apparatus, there is an image pickup method called an interlace scanning method by a simultaneous method. A color image based on this imaging method forms a frame image with a pair of odd field and even field images.

However, according to the imaging method, in an example in which the movement of the subject is strong when the freeze image is obtained, the image shift occurs due to the time difference between the odd and even fields, which causes flicker on the display screen and makes the image difficult to see. Become.

Therefore, conventionally, in order to avoid the above-described image shift, only one field image is always displayed as a freeze image on the display screen.

(Problems to be Solved by the Invention) However, when a freeze image is always obtained with only one field image as in the conventional case, it is possible to prevent flicker from occurring on the display screen, but on the other hand, this kind of problem However, the vertical resolution of the camera of the endoscopic device is used only half, and thus the resolution of the frozen image is deteriorated.

The present invention has been made to solve the above problems, and an object thereof is to use a freeze image as a field image or a frame image according to the degree of movement of a subject at the timing of recording the freeze image. An object is to provide an endoscope apparatus capable of automatically selecting whether to use an image.

[Structure of the Invention] (Means for Solving the Problems) In order to achieve the above object, the present invention provides an endoscope apparatus capable of displaying an image collected by an image pickup means as a frozen image. An image selecting means for selectively selecting one of a field image and a frame image when recognizing a shift between the image and the field is provided, and an image corresponding to the selection content of the image selecting means is displayed or recorded. It is characterized by

(Operation) With the endoscope device having such a configuration, when a freeze instruction is given, either the frame image or the field image is used as a freeze image depending on whether the subject moves a lot or little. Since the selected image can be selected and displayed or recorded, an image with essentially high resolution can be obtained when the movement of the subject is small, and a high-quality image without blur can be obtained when the movement of the subject is large. .

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

In the endoscope apparatus of this embodiment, the light emitted from the light source 2 is sent to the light guide 5 via the optical chopper 3 driven by the motor 4, and the distal end portion of the endoscope 1 is directed to a subject (not shown). The CCD image pickup device 6 provided at the tip of the endoscope 1 receives the light reflected by the irradiation and converts it into an electric signal.

Then, a TV camera circuit 7 for converting the output signal of the CCD image pickup device 6 into a color video signal, an A / D converter 8 for digitally converting the video signal from the TV camera circuit 7, and this A / D converter 8 An image memory 9 which takes in the digitally converted image data from the image memory, and the image data in the image memory 9 is converted into an analog signal and sent to the image monitor 14 and the VTR 15.
In addition to the basic operation parts of the / A converter 13, an arithmetic unit 10, a timing generator 11, and a freeze instruction push button switch 12 are provided to control these basic operation parts.

The details of the interrelationship between the memory 9, the arithmetic unit 10 and the timing generator 11 are shown in FIG.
In the figure, 91 is an image memory for storing an odd field image, 92 is an image memory for storing an even field, 10
1 is a SUB circuit having a circuit configuration for calculating an image difference between an odd field and an even field, 102 is a SUM circuit having a circuit configuration for adding the difference for each pixel obtained in the SUB circuit 101 in the image space, and 103 is a SUM circuit 102 It is an SH circuit that compares the output of the threshold value with the threshold value K.

Further, the timing generator 11 triggers a freeze signal and executes writing and reading control of the memory 9 according to the output signal of the SH circuit 103.

Next, the operation will be described. As shown in FIG. 3, in the case of interlaced scanning, the state of synchronization between the video signal and the optical pulse is determined by the vertical synchronization signal VD in the odd field (O),
The even field (E) is repeated.

At that time, to prevent flickers from occurring in the frozen image,
It is necessary to eliminate the time difference between the signal storage periods of the odd field and the even field.

Therefore, as shown in FIG. 3, the light of the light source 2 is intermittently pulsed by the optical chopper 3 so that the light (light) pulse extends over the end of the odd field and the start of the even field. The image of the odd field is collected by the light irradiation of the even field in the figure.

Therefore, in this embodiment, the field image and the frame image are switched as described in detail below.

First, the light emitted from the light source 2 is output by the optical chopper 3.
It is guided to the light guide 5 as pulsed light which becomes the light pulse of FIG. Light chopper 3
The timing is realized by the drive motor 4 controlled by the timing generator 11.

The reflected light from the subject is converted into an electric signal by the CCD image pickup device 6 and further converted into a video signal by the TV camera circuit 7. This video signal is digitally converted by the A / D converter 8 and temporarily stored in the memory 9, and then the D / A converter 1
Converted to analog signal by 3 and display 14 and V
It is sent to TR15. Therefore, the contents picked up by the CCD image pickup device 6 are displayed on the display 14 and recorded in the VTR 15.

At this time, the memory 91 of the memory 9 stores the odd field image data, and the memory 92 stores the even field image data. And push button switch 12
When the freeze signal is generated, the memory 9 is prohibited from storing new image data and freezes the stored image data.

Then, the image difference between the odd field image and the even field image is calculated by the SUB circuit 101, and the image difference is added by the SUM circuit 102 over the entire screen, for example. This amount of addition represents the degree of image shift between the odd field image and the even field image. Further, this addition amount is compared by the SH circuit 103 with a threshold value K at which flicker is noticeable when an image is displayed.

If the comparison result in the SH circuit 103 is larger than the threshold value K,
Of the image data stored in the memory 9, the image data of one field, for example, the odd field, is read out, and the content showing the read-out image data is displayed on the image monitor 14.

On the contrary, if it is smaller than the threshold value K, the odd-numbered field image data and the even-numbered field image data are read from the memory 9 and displayed and recorded as a frame image.

As described above, in this embodiment, the subject is irradiated with the light pulse so that the image shift between the odd-numbered field image and the even-numbered field image is reduced as much as possible, and if the image shift is still large, The one-field image is automatically displayed and recorded as a freeze image in response to the freeze instruction. Then, when the displacement of the image is small, the frame image is displayed and recorded as it is as a freeze image.

Further, in this embodiment, in order to determine whether the image shift between the odd-numbered field image and the even-numbered field image is large or small, the image is electrically processed using the video signal obtained by imaging. The operator can see the monitor easily (instantly) based on visual judgment.

In the case of image shift determination based on this visual determination, a mode switching function that switches the freeze image displayed in the frame image to the freeze image displayed in the field image by a predetermined input operation such as pressing the freeze button again. A controller (not shown) may be provided in the system configuration to achieve image selection depending on the degree of image misalignment.

As described above, as one embodiment of the present invention, the location of the electronic endoscope device in which the CCD image pickup device is provided at the tip portion of the endoscope is exemplified, but for example, an image pickup camera is usually provided in the eyepiece portion of the fiberscope. Of course, the present invention can be applied to any of the above endoscope devices.

That is, even in the case of this normal endoscope apparatus, the image selecting means for selectively selecting one of the field image and the frame image when the shift between the images of the odd field and the even field is recognized at the time of freezing. By providing the above, as in the embodiment of the present invention described above, when the movement of the subject is small, an image with essentially high resolution is obtained, and when the movement of the subject is large, a good-quality image without blurring is obtained. be able to.

[Effects of the Invention] As described above, the endoscope apparatus to which the present invention is applied selects one of a field image and a frame image when recognizing an image shift between an odd field and an even field during freezing. Since the selection is made in one step, when the movement of the subject is strong, the one-field image can be used as the freeze image. When the movement of the subject is less than normal, a frame image with high resolution and no flicker can be used as the freeze image. Can be used.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of an embodiment of an endoscope apparatus to which the present invention is applied, FIG. 2 is a block diagram showing a configuration of main parts in the embodiment, and FIG. 3 is a timing of light pulse irradiation. 2 is a time chart schematically showing. 1 ... Endoscope, 2 ... Light source 91 ... Odd field memory 92 ... Even field memory 101 ... Difference calculator, 102 ... Adder 103 ... Comparator, 11 ... Timing generation circuit

Claims (3)

[Claims] 1. An endoscope apparatus capable of displaying an image collected by an image pickup means as a freeze image, and when a shift between images of an odd field and an even field is recognized at the time of freezing, one of a field image and a frame image is recognized. An endoscopic device characterized by comprising image selecting means for selectively selecting, and displaying or recording an image according to the selection content of the image selecting means. 2. The endoscope apparatus according to claim 1, wherein the image selecting means detects an image difference between an odd field image and an even field image based on a video signal obtained by photographing. . 3. The image selecting means, in response to a predetermined input operation for selecting a frame image and a field image, selectively selects one of the frame image and the field image. The endoscope apparatus according to claim 1.