JPH09253041A - Endoscope system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To clearly observe an observation object part under consideration corresponding to various object states in an endoscopic inspection. SOLUTION: The image of an object is formed at a solid-state image pickup element by an objective lens system 11 provided with a lens 13 for focusing at the tip part of an electronic endoscope 2, the output signals of the solid-state image pickup element are inputted to a post processing circuit 16 inside a video processing circuit 4 and the image data of the high frequency components of luminance signals are tentatively stored in the memory 10 of a focus mode selection circuit 17. Then, when one of plural circuits 17a, 17b,... is selected by the selection of a selection switch 19, a focus detection circuit 18 performs focus detection by a focus detection area set by the selected circuit, and by moving the lens 13 for focusing to a focus state through a focus driving device 6 by the output, a state capable of clearly observing the observation object part in the respective object states is set even in the case of the variously different object states.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an endoscope apparatus having an autofocus function for setting an in-focus state with respect to an output signal of an image pickup means having a focusing lens.

[0002]

2. Description of the Related Art Recently, an image pickup apparatus using a solid-state image pickup device such as a CCD has been widely used. In this image pickup device, the focus state is automatically set (focus state).
As a conventional example of a device having the function of setting to, there is, for example, JP-A-5-91390.

In this conventional example, a reference dead time for a focus operation is set for each circuit, and the reference dead time can be changed by switching a mode setting switch.
Even if the shooting distance is constantly changing, a stable focus state can be maintained. In this conventional example, in a general video camera, the focus response time can be changed so as to correspond to only the change in the shooting distance.

[0004]

When the above conventional example is applied to an endoscope for observing the inside of a body cavity, it is difficult to obtain a desired good image. When observing the inside of a body cavity, the subject distance may be constantly changing, and in many cases, an endoscopic image in which the subject distance is very different is observed. That is, in endoscopy, an objective optical system with a wide field of view (usually 90 ° or more) is adopted so that the lesion site can be observed without being overlooked.
There may be a case where a very different object distance such as a near point (3 mm) to a far point (150 mm) is simultaneously displayed on the screen.

Further, in the case where the lesion site is examined while moving along the lumen, the central part of the image may be the lumen part and the observation target part may be the peripheral part thereof. When only the central area of the image is fixed to the focus detection area, it becomes difficult to clearly observe the desired observation target site.

In addition, a treatment tool such as biopsy forceps may be used for examination and treatment of a lesion, and when the treatment tool is displayed in the endoscopic image, the treatment tool is used. It is desirable not to be an obstacle to focus adjustment.

On the other hand, as a conventional example having a focus adjusting function in the field of endoscope, for example, Japanese Patent Application Laid-Open No. 6-11831.
4, JP-A-5-341209, etc., which disclose an actuator at the tip of an endoscope, and JP-A-2-3044.
As disclosed in Japanese Patent No. 13, a switch provided with a switch for stopping the control means for automatic focus adjustment is disclosed. However, it has an automatic focus adjustment function that can appropriately cope with different subject states. No technology is disclosed.

The present invention has been made in view of the above-mentioned points, and has an automatic focusing function capable of clearly observing a target observation target portion in accordance with various subject states in an endoscopic examination. An object is to provide a mirror device.

[0009]

A focusing lens, a solid-state imaging device, and an actuator for driving the focusing lens are provided at the tip of an insertion portion, and a signal from the solid-state imaging device is converted into a video signal. In an endoscopic device having a video process device for performing processing and a focus driving device for driving an actuator, at least a focus detection circuit for determining the focus of an image of a subject from an output signal from a solid-state image sensor, By providing a plurality of circuits that define the focus detection area and a selection unit that selects the plurality of circuits, by selecting the circuits by the selection unit, the focus detection areas suitable for various different subject states can be used. The observation target area of is clearly visible.

Further, a video having a focusing lens, a solid-state image sensor, and an actuator for driving the focusing lens at the tip of the insertion section, and performing processing for converting a signal from the solid-state image sensor into a video signal. In an endoscope apparatus having a process device and a focus drive device for driving an actuator, a focus detection circuit for determining the focus of an image of a subject from an output signal from a solid-state image sensor, and the focus detection circuit. Even if the subject information is different, the corresponding focus detection area etc. are automatically set by providing the automatic focus adjustment device that performs the focusing operation corresponding to the subject information based on the signal from the subject and the subject information. In this way, the observation target part of the subject can be clearly observed.

[0011]

Embodiments of the present invention will be described below in detail with reference to the drawings. (First Embodiment) FIGS. 1 to 6 relate to a first embodiment of the present invention. FIG. 1 shows the configuration of an endoscope apparatus according to the first embodiment, and FIGS. Shows a focus detection area and a typical subject state corresponding thereto, and FIG. 6 shows a responsiveness relationship set corresponding to the blur amount.

As shown in FIG. 1, an endoscope apparatus 1 according to the first embodiment of the present invention includes an electronic endoscope 2 having an image pickup means at the distal end portion of an insertion portion, and the electronic endoscope 2. A light source device 3 that supplies illumination light, a video process device 4 that performs signal processing for the image pickup means, a color monitor 5 that displays a video signal output from the video process device 4, and a video process device 4 that outputs the video signal. Drive control signal
The focus driving device 6 sets the objective lens system in a focused state (focused state).

The electronic endoscope 2 has an elongated insertion portion 7 and a light guide 8 for transmitting illumination light to the insertion portion 7.
The rear end of the light guide 8 is connected to the light source device 3 so that the illumination light supplied from the lamp 9 in the light source device 3 is transmitted and fixed to the illumination window at the tip of the insertion portion 7. It is emitted from the tip surface and illuminates the subject side such as the affected area.

The illuminated object is solid-state imaging device 1 such as a charge-coupled device (abbreviated as CCD) by an objective lens system 11 attached to an observation window formed adjacent to the illumination window.
An image pickup signal corresponding to the optical image of the subject is output after being image-formed on No. 2 and subjected to photoelectric conversion. The objective lens system 11 has a focusing lens 13 movable in the optical axis direction, and the focusing lens 13 is moved in the optical axis direction by an actuator 14 driven by a drive signal from the focus driving device 6. By the objective lens system 11, it is possible to variably set the image formation state of the optical image formed on the solid-state image sensor 12, that is, the non-focus state or the focus state.

The image pickup signal outputted from the solid-state image pickup device 12 is inputted to the preprocess circuit 15 in the video process device 4, and after being adjusted for γ correction and white balance, it is inputted to the postprocess circuit 16. , For example NT
A video signal such as an SC composite video signal is generated and output to the color monitor 5, and the subject image is displayed in color on the monitor screen 5A.

Further, the post-process circuit 16 further applies, to the focusing mode selection circuit 17, signal data (or image data) obtained by A / D converting a signal obtained by extracting a high frequency component of the luminance signal (by a high pass filter or the like). It is output and temporarily stored in the memory in the focus mode selection circuit 17.

The focus mode selection circuit 17 corresponds to a plurality of subject states and performs a focus detection or the like in a focus detection area suitable for each subject state (automatic focus adjustment mode).
A plurality of circuits for selectively setting (or defining) (first circuit 17a, second circuit 17b, third circuit 17c,
, And circuit 17i (i = a, b, c,
...).

The focus detection circuit 18 focuses on or deviates from the focus state with respect to the image data in the focus detection area designated by each circuit 17i of the focus mode selection circuit 17 (abbreviated as blur amount). ) Is detected and a movement signal corresponding to the blur amount is output to the focus driving device 6, and the focus driving device 6 performs current amplification or the like to output the driving signal to the actuator 1.
4, the focus lens 13 is moved in the optical axis direction by the actuator 14 to reduce the blur amount, and the objective lens system 11 is set to the in-focus state with respect to the solid-state image sensor 12.

Further, in the video process device 4, for example, a selection switch 19 is provided on an operation unit such as a front panel.
Is provided, and one of the plurality of circuits 17i in the focus mode selection circuit 17 can be designated by selecting or designating the circuit 17i from the selection switch 19.

Further, by selecting the selection switch 19, the circuit 17i of the focus mode selection circuit 17 outputs to the focus drive device 6 a response control signal for variably setting the responsiveness for setting the focus state according to the blur amount. The characteristics of a filter circuit provided inside the focus driving device 6 for determining the responsiveness are varied according to the response control signal.

The electronic endoscope 2 has a channel 21 through which a treatment tool such as the biopsy forceps 20 is inserted.
With the biopsy forceps 20 protruding through the device, a procedure such as biopsy can be performed.

The focus detection area 22 designated by each of the circuits 17i is shown in FIGS. These focus detection areas 22 are preset in correspondence with typical subject states in the case of an endoscopic examination, and the focus detection areas 22 respectively corresponding to the typical subject states are set.
By performing the focus detection and the focus setting, the subject such as the observation target region 23 in that case can be clearly observed.

That is, FIGS. 2 to 5A each show the focus detection area 22 in the endoscopic image 24 displayed on the monitor screen 5A, and each focus detection area 22 is shown in FIG. It is set corresponding to a typical subject state. According to a subject state that corresponds to or is similar to a typical subject state, focus detection is performed by a focus detection area 22 suitable for observing the observation target region 23 in the subject state, and the focus detection is performed. In the area 22, it is possible to select to perform the operation of setting the focus state.

2 and 3, the focus detection areas 22 suitable for observing the observation target region 23 shown in FIG. 2B are set so as to correspond to each other, and the focus detection areas 22 are adjusted. Although the automatic focus adjustment is performed so as to set the focus state, in FIG. 4, the focus detection area 22 in the center for performing focus detection and the like as in FIGS. 2 and 3 is used together with the focus detection area. A focus detection area 22 'that is used as an area but is not set to the in-focus state is adopted.

In this case, when the focusing lens 13 is moved with respect to the subject side, the observation target portion 23 corresponding to the central focus detection area 22 is focused (the amount of blurring becomes small). If it cannot be determined whether or not the focus detection area 22 can be set, it is possible to more reliably observe by referring to the blur amount in the focus detection areas 22 ′ set in the four corners in addition to the focus detection area 22. Focus detection and focus setting that enable the target region 23 to be clearly observed are possible.

For this reason, the focus detection detection area 22 'may be similarly employed in other subject states. Also,
FIG. 5 (A) shows an image when forceps corresponding to the two typical focus detection areas 22 are used, and one focus detection area on the side where the forceps are observed is set. There is.

That is, specifically, the observation window and the channel 2
When the forceps are observed depending on the arrangement of No. 1, it is determined whether the forceps are projected from the lower right position to the vicinity of the center or the forceps are projected from the lower left position to the vicinity of the center. The focus detection area 22 corresponding to the observation target portion 23 including the tip of the forceps can be selected (in the case of FIG. 5, if the endoscope is determined, the focus detection area 22 can be selected from the two focus detection areas 22). On the other hand it will be good).

In the present embodiment, in the case of endoscopy,
Since there are various different subject states, in order to correspond to each of them, for each subject state,
One of the features is that a circuit 17i for controlling focus detection or the like in the focus detection area 22 most suitable for observation is prepared, and one of them can be selected by the selection switch 19. It has become.

Further, FIGS. 6A to 6C show characteristics defining the response Y to the detected blur amount X. Here, Xo represents a reference blur amount set at about the boundary of the depth of focus, and its characteristic is set according to the circuit 17i designated by the selection switch 19.

In FIG. 6A, when the blur amount is smaller than the reference blur amount Xo, the response is set to almost 0 within the depth of field, and when the blur amount is larger than the reference blur amount Xo as a boundary. Indicates that the response speed is maximized, and the response has a response that sharply changes with the value of the reference blur amount Xo.

Further, FIG. 6B shows that the response speed is slow when the blur amount is small, and the response speed is sharply increased according to the increase of the blur amount when the blur amount is larger than this.
Further, when the blur amount is larger than the intermediate value, the response speed is increased slowly.

When observing a moving flat part or the like, the responsiveness is set to almost 0 (a response speed relatively slower than the motion such as pulsation) as shown in FIG. Therefore, the in-focus state does not change and the in-focus state can be maintained. As described above, in the present embodiment, the circuit 1 that defines the focusing mode by the selection switch 19 is used.
When 7i is selected, the responsiveness to the focus detection area and the blur amount is determined according to the selected circuit 17i, for example, as shown in the table below. Settings other than this table may be set.

Table Selected Circuit Focus Detection Area Responsiveness Typical Application Site First Circuit FIG. 2 (A) FIG. 6 (B) Stomach Second Circuit FIG. 3 (A) FIG. 6 (B) Esophagus, Bronchus 3 circuits FIG. 3 (A) FIG. 6 (A) Large intestine, biliary tract Fourth circuit FIG. 2 (A) FIG. 6 (C) Body cavity inner planar part Fifth circuit FIG. 3 (A) FIG. 6 (C) Lumen general sixth Circuit FIG. 5 (A) FIG. 6 (B) Seventh circuit when a treatment tool is used FIG. 4 (A) FIG. 6 (B) Slope portion The operation of the endoscope device 1 having such a configuration will be described below.

When observing the inner wall of the esophagus or the inner wall of the stomach through the electronic endoscope 2 through the body cavity, for example, the esophagus, the state corresponding to FIG. 3B is selected when observing the inner wall of the esophagus. By selecting the third circuit 17c with the switch 19, the focus detection area 22 is shown in FIG.
The peripheral portion of the endoscopic image 24 of is selected.

By this selection, the third circuit 17c transfers (outputs) the image data stored in the memory in the focusing mode selection circuit 17 to the focusing detection circuit 18 and outputs the image data of the peripheral portion to the focusing detection circuit 18. The circuit 18 performs focus detection on the transferred image data of the peripheral portion. This image data is a high frequency component in the luminance signal, and the focusing lens 13 is moved in the optical axis direction so that the integrated value thereof becomes maximum. A so-called hill-climbing focus detection and focus setting is performed.

When the focus detection circuit 18 cannot determine the degree of blur and the moving direction for reducing the blur as in the initial state, for example, a temporary movement signal (for example, a stepwise signal or a sawtooth signal). Signal) is output, and the degree of blurring or in which direction the blur is occurring is determined based on the amount of change in the integrated value of the image data detected before and after the movement signal. Further, by outputting several steps-like signals, it is possible to detect the state in which the integrated value is maximum, and the integrated value in which the maximum is obtained is in focus, and the blur amount X
Is set to 0.

When the integral value of the in-focus state is determined in this way, the blur amount is estimated from the integrated value, and the actuator 14 is driven at a response speed or the like according to the blur amount to focus in the focus detection area. The focus state is set so that

Specifically, the central portion of the lumen is not used for focus detection, but its peripheral portion is set as the focus detection area 22 as shown in FIG. 3A, and this focus detection area 22 is set. When the focusing lens 13 is moved in the optical axis direction so that the image becomes in focus, the amount of blur is minimized (or the integrated value of the image data (extracting the high frequency component of the luminance signal) is maximized). Set the focus state. In this case, when the actuator 14 is driven, it is driven with the responsiveness of the characteristic as shown in FIG. 6 (B).

When the inner wall of the esophagus is observed in this way,
The inner wall portion of the esophagus can be observed more clearly (compared to the case where the entire image is used as the focus detection area or the center portion of the image is used as the focus detection area).

In the case where the inner wall of the stomach is to be observed and the inner wall of the stomach is to be observed, the first switch 17a, for example, is selected by the selection switch 19 when the convex portion of the inner wall is observed, and the inner wall of the sloped surface is selected. When observing the portion, for example, the seventh circuit 17g is selected.

In this way, the selection switch 1 is selected according to the subject state to which the observation target region 23 to be observed belongs.
By selecting by 9, it is possible to observe the observation target portion 23 in a state suitable for clear observation.

When the treatment is performed using forceps, by selecting the sixth circuit 17f by the selection switch 19, the tip portion of the forceps can be observed in a observable state and the tip portion of the forceps other than the tip portion can be observed. The portion near the base end can be excluded from the focus detection area, and the tip portion of the forceps and the portion treated by the tip portion can be set in the focused state and observed.

As described above, according to the present embodiment, by the selection instruction by the selection switch 19 according to the subject state,
It is possible to select one of the plurality of circuits 17i and set the focus state in the focus mode such as the focus detection area defined by the selected circuit.

(Second Embodiment) FIGS. 7 and 8 relate to a second embodiment of the present invention. FIG. 7 shows an endoscope apparatus according to the second embodiment, and FIG. The representative area | region of the focus detection in an endoscopic image is shown. The endoscopic device 31 of the present embodiment shown in FIG. 7 employs a video process device 34 having a configuration different from that of the video process device 4 in the endoscopic device 1 shown in FIG.

In the video processing device 34, the post-process circuit 16 outputs the image data of the high frequency component extracted from the luminance signal in the video signal corresponding to the endoscopic image to the focus detection circuit 18, and this focus detection circuit Reference numeral 18 denotes a plurality of representative areas 24a, 24b, ..., 2 obtained by dividing almost the entire area of the endoscopic image 24 except for the periphery thereof as shown in FIG.
The blur amount at 4z is detected and output to the subject information analysis circuit 32.

The subject information analysis circuit 32 analyzes the subject information (specifically, the amount of blur data) detected by the focus detection circuit 18, and determines which of a plurality of typical subject states it corresponds to. to decide. This determination is made, for example, by being provided in the subject information analysis circuit 32 and collated with the stored information of the ROM 33 that stores the subject information such as the distribution pattern of the blur amount in each of a plurality of typical subject states, or by correlation detection. , Which typical subject state the detected blur amount data most corresponds to is obtained by calculation or the like (for this reason, the subject information analysis circuit 32 also has a computing unit).

For example, the distribution pattern of the blur amount is arranged according to the distance from the representative region 24s near the center of the endoscopic image 24 in FIG. 8 (or the distribution pattern of the magnitude of the integral value of the image data is arranged. , How similar integral values are distributed) and perform calculations such as matching with the case of a typical subject state to determine which of the multiple typical subject states is the closest. to decide.

The post-process circuit 16 also outputs a luminance signal to the forceps detection circuit 35. The forceps detection circuit 35 responds to the input luminance signal in a typical endoscopic image in which forceps are observed. Whether a luminance signal exceeding a preset high luminance value is detected in a plurality of image regions in which forceps are likely to exist (for example, the lower right strip portion and the lower left strip portion in FIG. 3A). The presence or absence of forceps is determined by detecting whether or not forceps are present.

Generally, the forceps has a high-luminance image because the surface is formed of a member having a high reflectance, and therefore it is judged whether or not a portion exceeding a preset high value is detected in a strip shape or a wedge shape. Therefore, it is possible to determine the presence or absence thereof. The signal that detects the presence or absence of the forceps is input to the subject information analysis circuit 32 and used for analyzing and determining the subject state.

The subject information analysis circuit 32 has a plurality of circuits 32j (j = a, b, c, ...) Which define a focus detection area or the like set corresponding to the determined subject state. Then, typical subject information by the ROM 33,
After determining the subject state from the endoscopic image information with reference to the detection result of the forceps detection circuit 35, the subject information analysis circuit 32 defines the circuit 32k corresponding to the determined state, and the defined circuit In 32k, the image data input from the post-process circuit 16 to the focus detection circuit 18 is
Control is performed by opening and closing the gate so that only the focus detection area corresponding to the subject state determined by the subject information analysis circuit 32 is provided.

As the focus detection areas corresponding to a plurality of subject states, for example, FIGS. 2 to 5 in the first embodiment are used.
The focus detection area 22 as shown in FIG. Therefore,
After that, the focus detection circuit 18 detects the blur amount in the focus detection area defined by the circuit 32k, and outputs a drive control signal corresponding to the blur amount to the focus drive device 6.

That is, in this embodiment, the subject information analysis circuit 32 automatically determines the subject state using the output signal of the focus detection circuit 18, and selects the circuit 32k corresponding to the determined subject state. Then, the actuator 14 is driven in the focusing mode defined by the circuit 32k to set the focusing state. Therefore, the selection switch 1 in FIG.
Do not have 9. Other configurations are the same as those in FIG.

The operation of this embodiment is as follows.
The focus detection circuit 18 first outputs an integrated value of image data in a plurality of representative areas obtained by dividing almost the entire endoscopic image into a plurality of pieces, to the subject information analysis circuit 32. The subject information analysis circuit 32 analyzes the array of the distribution patterns of the input integrated values, determines which subject state corresponds, and selects or specifies the corresponding circuit 32k according to the determination result.

When the circuit 32k is selected, the circuit 32k judges the image data output from the post-process circuit 16 based on the image data input to the focus detection circuit 18 by the subject information analysis circuit 32. Control is performed by opening and closing the gate or the like so that only the focus detection area corresponding to the subject state is performed. Then, after that, the focus detection circuit 18 detects the blur amount only in the focus detection area defined by the circuit 32k, and outputs a drive control signal corresponding to the blur amount to the focus drive device 6 to drive the actuator. 14 is driven to automatically set the objective lens system 11 to the in-focus state.

In the present embodiment, the image information obtained from the solid-state image pickup device 12 is analyzed to determine the subject state, and a focus detection area or the like suitable for observing an observation target portion in the subject state is automatically determined. Since the setting is made dynamically, the same effect as that of the first embodiment can be obtained without the operator making a selection.

(Third Embodiment) FIG. 9 shows a third embodiment of the present invention.
The endoscope apparatus 41 of the embodiment of FIG. The endoscopic device 41 of the present embodiment employs a video process device 44 having a configuration different from that of the video process device 34 in the endoscopic device 31 shown in FIG. 7.

In the video process device 44, the post process circuit 16 generates R, G, B color signals and outputs them to the color monitor 5 together with the synchronizing signals. Further, the R and B color signals are input to the focus detection circuit 43 via the image detection circuit 42.

The image detection circuit 42 compares the levels of the R and B color signals, selects the larger color signal, and outputs it to the focus detection circuit 43. The focus detection circuit 43 detects the state of the image by the input color signal, for example, by the contrast method, and outputs it to the subject information analysis circuit 46.

The R, G, B color signals generated by the post-process circuit 16 are input to the forceps detection circuit 45,
It is detected whether forceps are present in the image region set by the luminance signal obtained by weighting and adding the R, G, and B color signals, and the signal that detects the presence or absence is output to the subject information analysis circuit 46. To do.

The subject information analyzing circuit 46 defines a ROM 47 in which typical blur data or contrast value distribution data of a subject state according to the contrast method is stored in advance, and a focus detection area set corresponding to the subject state. It has a plurality of circuits 46j (j = a, b, c, ...) And an arithmetic unit for analyzing subject information.

Then, the subject information analysis circuit 46 determines the subject state from the output signal of the focus detection circuit 43 and the output signal of the forceps detection circuit 45 as in the second embodiment. After detecting the subject state, the circuit 46k corresponding to the subject state is selected, and the focus setting is performed by the circuit 46k.

In the present embodiment, the focus detection circuit 43 constantly outputs a signal of the contrast value for a specific color signal corresponding to the entire image to the circuit 46k in the subject information analysis circuit 46, and this circuit 46k. Only the signal portion of the corresponding focus detection area is extracted, the focus state or the blur amount is detected by comparison with the signal portion one frame before, and a drive control signal is output to the focus drive device 6. The present embodiment has substantially the same operation and effect as the second embodiment.

In the second embodiment, for example,
When the subject information analysis circuit 32 analyzes the subject information (endoscope information) and determines that the analysis result may be a plurality of subject states instead of the typical one subject state (for example, a plurality of subject states). When it is determined that a typical subject state is a mixed state such as a weighted average, the subject information analysis circuit 32 weights the focus detection areas of a plurality of corresponding circuits according to the weight of the determination result. Then, it may be used for focus detection and focus setting.

Further, it is also possible to perform control such that a focus mode is set and focus detection and focus setting are performed by fuzzy inference based on the analysis result of subject information. For example, from the blur amount detected in each of the representative regions 24a, 24b, ..., 24z in FIG. 8, the characteristics of the focus detection region according to information such as the spread (or size) of the focus portion or the distribution of the blur amount. It is also possible to set a membership function for setting and set the focus detection area by fuzzy inference according to the detected information.

More specifically, the representative areas 24a, 24
b, ..., 24z, when the areas having the same degree of blurring are wide, the focus detection area is set wide, and conversely, when the area is narrow, the focus detection area is set narrow. Set the membership function.

When the distribution of the brightness level is detected and the dark part is detected on the center side, the focus detection area is set on the peripheral side, and the part where the brightness level is dark is detected on the peripheral side. Is set to the membership function of a rule that sets the focus area to the center side.

The focus detection area may be set by fuzzy inference using these membership functions. Further, for the responsiveness, a membership function or the like may be defined to control the responsiveness of the operation mode when the focus state is set.

In the above description, the electronic endoscope 2 having the solid-state image pickup element built-in at the tip is explained, but the tip surface of the image guide as the image transmitting means is arranged at the position of the solid-state image pickup element. In the case of an endoscope equipped with a TV camera, which includes the optical endoscope and a TV camera that is detachably connected to the eyepiece of the optical endoscope and has a built-in solid-state image sensor for photoelectric conversion. The same applies.

The actuator 14 is not necessarily limited to the one arranged at the tip of the insertion portion.
The operation mode set to the focused state may be determined by the response of the actuator. It should be noted that embodiments and the like configured by combining the above-described embodiments and the like in a partial manner also belong to the present invention.

[Additional Notes] 3. The endoscope apparatus according to claim 1, wherein the focus detection circuit performs focus detection using a central portion of the image as a focus detection area. 4. The endoscope apparatus according to claim 1, wherein the focus detection circuit performs focus detection using a peripheral portion of the image as a focus detection area. 5. The endoscope apparatus according to claim 1 or 2, wherein the focus detection circuit performs focus detection using a center portion and four corners of the image as focus detection areas.

6. The endoscope apparatus according to claim 1, wherein the focus detection circuit performs focus detection using a lower right portion or a lower left portion of the image corresponding to the protrusion of the forceps as a focusing detection region. 7. The endoscope apparatus according to claim 1, wherein a constant focus drive signal is output regardless of the blur amount of the image detected by the focus detection circuit. 8. 3. The response characteristic according to claim 1, wherein the focus operation is slow when the blur amount of the image detected by the focus detection circuit is small or large, and the agile focus operation is performed when the blur amount is intermediate. Endoscopic device.

9. The endoscope apparatus according to claim 1 or 2, wherein the operation mode set to the in-focus point is determined by the response of the detection area and the actuator. 10. A video process device that has a focusing lens, a solid-state image sensor, and an actuator for driving the focusing lens at the tip of the insertion section, and that performs a process of converting a signal from the solid-state image sensor into a video signal. In an endoscope apparatus having a focus drive device that drives an actuator by the output of a focus detection circuit that detects whether or not a focus state is present, the observation state of a plurality of different subjects that are typically different from the output signal from the solid-state image sensor is determined. Is provided, the focus detection area by the focus detection circuit is defined by the output of the focus detection circuit, and the focusing lens is driven so as to be in focus in the focus detection area. Endoscopic device.

[0073]

As described above, according to the present invention, the focusing lens and the solid-state image sensor are provided at the tip of the insertion portion.
An endoscope apparatus having an actuator for driving the focusing lens, a video process device for converting a signal from a solid-state image sensor into a video signal, and a focus driving device for driving the actuator. In, a focus detection circuit for determining the focus of an image of a subject from an output signal from the solid-state image sensor, a plurality of circuits for defining at least a focus detection area, and a selection unit for selecting the plurality of circuits are provided. Therefore, by selecting the circuit by the selecting means, the observation target region of the subject can be clearly observed by the focus detection regions suitable for various different subject states.

Further, a video which has a focusing lens, a solid-state image pickup element, and an actuator for driving the focusing lens at the tip of the insertion section, and which carries out processing for converting a signal from the solid-state image pickup element into a video signal. In an endoscope apparatus having a process device and a focus drive device for driving an actuator, a focus detection circuit for determining the focus of an image of a subject from an output signal from a solid-state image sensor, and the focus detection circuit. Since the automatic focus adjustment device that performs the focusing operation corresponding to the subject information based on the signal from the subject and the subject information is provided, even when the subject information is different, the corresponding focus detection area and the like are automatically detected. By setting, you can clearly observe the observation target part of the subject.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing a configuration of an endoscope apparatus according to a first embodiment of the present invention.

FIG. 2 is a diagram showing a focus detection area and a typical subject state corresponding thereto.

FIG. 3 is a diagram showing a focus detection area and a typical subject state corresponding thereto.

FIG. 4 is a diagram showing a focus detection area and a typical subject state corresponding thereto.

FIG. 5 is a diagram showing a focus detection area and a typical subject state corresponding thereto.

FIG. 6 is a characteristic diagram showing a relationship of responsiveness set corresponding to a blur amount.

FIG. 7 is a configuration diagram showing a configuration of an endoscope apparatus according to a second embodiment of the present invention.

FIG. 8 is a diagram showing a plurality of representative regions in which focus detection is performed.

FIG. 9 is a configuration diagram showing a configuration of an endoscope apparatus according to a third embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Endoscope device 2 ... Electronic endoscope 3 ... Light source device 4 ... Video process device 5 ... Color monitor 6 ... Focus drive device 7 ... Insertion part 11 ... Objective lens system 12 ... Solid-state image sensor 13 ... Focusing lens 14 ... actuator 16 ... post-process circuit 17 ... focus mode selection circuit 18 ... focus detection circuit 19 ... selection switch 20 ... biopsy forceps 21 ... channel

Claims (2)

[Claims] 1. A video having a focusing lens, a solid-state imaging device, and an actuator for driving the focusing lens at the tip of the insertion portion, and performing processing for converting a signal from the solid-state imaging device into a video signal. Process equipment,
In an endoscope apparatus having a focus drive device for driving an actuator, a focus detection circuit that determines the focus of an image of a subject from an output signal from a solid-state image sensor and at least different focus detection areas are defined. An endoscope apparatus, comprising: a plurality of circuits for selecting the plurality of circuits; and a selection unit for selecting the plurality of circuits, and performing a focusing operation by the circuit selected by the selection unit. 2. A video having a focusing lens, a solid-state image sensor, and an actuator for driving the focusing lens at the tip of the insertion section, and performing processing for converting a signal from the solid-state image sensor into a video signal. Process equipment,
In an endoscope apparatus having a focus drive device for driving an actuator, a focus detection circuit that determines the focus of an image of a subject from an output signal from a solid-state image sensor, and a signal from the focus detection circuit An endoscope apparatus comprising: an automatic focusing adjustment device that causes a focusing operation corresponding to the subject information based on the subject information.