JPH08136814A - Focusing device for operating microscope apparatus - Google Patents

Abstract

PURPOSE: To make the device small in size and light in weight and to widely secure an operating space for an operator near the microscope body by setting a part of the variable range of focal distance as a basic operating region. CONSTITUTION: As operation progresses, an operating part reaches the depths of a celom from the surface of the celom. By operating a switch 6C for operating WD of a foot switch 6 by an operator in order to keep a distance between the tip part of a microscope body and the surface of the a celom in the operating part, a motor 11 is driven through a WD control circuit 10 and an objective lens driving circuit 9 and it is assumed that a focal distance is lengthened by 20mm by means of the mechanism 1 of an objective lens with variable focal distance. The displaced amount is detected by an encoder 12, the '20mm' is calculated by a first WD detecting circuit 13 and a focusing range is changed by a focusing range calculating circuit 15. Consequently, the operator appropriately sets the sight operating range again by using the switch 6C for operating WD of the foot switch 6 according to the progress of operation.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention particularly relates to a focusing device for a surgical microscope used for fine surgical operations.

[0002]

2. Description of the Related Art In recent years, with the development of surgical techniques and tools, microsurgery, which is performed while performing magnified observation using a surgical microscope, has become widespread, and is used in various fields such as neurosurgery, ophthalmology, and otolaryngology. It is being appreciated.

Focusing in a current surgical microscope is performed by moving a lens body by a supporting device or by moving a lens of a variable focal length objective lens mechanism in a lens body. The person uses both of them appropriately to perform focusing. The conventional focal length variable objective lens mechanism has a focal length adjustment range of, for example, 150 mm to 4 in order to secure a distance from the lower end of the mirror body to the body surface, that is, a working space.
It is as long as 00 mm so that it can be used for various subjects and surgery. This type of focusing device is disclosed, for example, in Japanese Patent Laid-Open Nos. 2-104349 and 6-175.
It is known in Japanese Patent Application No. 033 and Japanese Patent Application Laid-Open No. 5-346528.

[0004]

As described above, in the conventional focal length variable objective lens mechanism, a working space from the lower end of the mirror body to the body surface is secured, and various subjects and operations are performed. In order to cope with the above, the focal length adjustment range is also made long, for example, from 150 mm to 400 mm.

However, in reality, the instruments for the treatment are determined depending on each subject, the content of the surgery, and the surgical method, and accordingly, the focal length, that is, the working distance, is fixed to a certain degree. It is desirable to secure the distance. In order to solve this, JP-A-6-1750
In the description of the fourth embodiment of Japanese Patent No. 33, for example, in a situation shown in FIG. 9 of the accompanying drawings of the present application, a distance measuring means for measuring the distance between the body surface in the vicinity of the body cavity in the surgical site and the body portion It is separately provided to control the focal length by the variable focal length objective lens mechanism while keeping the distance between the body surface and the mirror unit constant. In the case of this method, if it is possible to measure on the observation optical axis of the mirror body, there is no problem, but it is difficult to measure on the observation optical axis in actual use. There are many. In addition, not only the operator's hand but also the assistant's hand and various surgical tools are often placed in the vicinity of the body cavity in the surgical site, and there are many obstacles in terms of measurement. Is.

Conventionally, as a method of effectively utilizing a finite focus adjustment range, Japanese Patent Laid-Open No. 2-104349 discloses a reset function. In this conventional device, as a focusing device, the mirror part is moved in the optical axis direction to perform focus adjustment, and since the reset position is also the center of the finite stroke, there is no need to change it during the operation. . However, in a variable focal length objective lens capable of varying the focal length over a wide range, resetting to the center value is meaningless, and actually the operability is impaired. This device is for changing the focus position without changing the position of the operator's eye, that is, the eye point, and should be set according to the progress of the operation.

Further, the operator roughly adjusts the focus when changing the observation site or the observation direction. However, if the reset function is operated, the actual focus is obtained during the observation. Adjusting to the position is not easy. The focus operation range is secured, but if the focus adjustment becomes ambiguous, the focus adjustment after positioning is originally designed to have a deep depth of focus, so the focus operation range may not be covered. . Therefore, it cannot be said that the reset function works effectively.

The present invention has been made in view of the above problems, and an object of the present invention is to more reliably secure an operating space for an operator in the vicinity of a mirror body and to improve its focusing operability. Another object of the present invention is to provide an inexpensive focusing device for a surgical microscope which has a good structure, a small size and a light weight, and a simple structure.

[0009]

DISCLOSURE OF THE INVENTION The present invention provides a variable focal length optical system including a plurality of lenses in a focusing device of a surgical microscope for automatically adjusting the focal length, and this optical system. A focal length changing means for changing the focal length within a variable focal length range by operating the detecting means, and a detecting means for detecting the adjusting operation of the focal length of the optical system by the focal length changing means and calculating the focal length thereof. Range selection means for selecting a part of the focal length variable range by the focal length variable means as a focusing operation range,
An operating means for performing an effective focal length varying operation in the focusing operation range selected by the range selecting means. According to this, a part of the focal length variable range in the variable focal length type optical system is set as the focusing operation range, and the focusing operation is performed within the selected specific focusing operation range. You can

[0010]

【Example】

<First Embodiment> A first embodiment of the present invention will be described with reference to FIGS. FIG. 1 shows a schematic structure of a body portion of a surgical microscope according to this embodiment, FIG. 2 shows a block structure of an electric system according to this embodiment, and FIG. 3 explains its operation.

(Structure) FIG. 1 shows a schematic structure of an optical system of the mirror body portion of the present embodiment. In FIG. 1, 1 is
It is a focal length variable objective lens mechanism that consists of multiple lenses, and the focal position of the observation object point can be changed by changing the lens interval, and at least a part of the optical system is moved to change the focal length of the optical system. It constitutes an adjustable focal length varying means. The variable focal length objective lens mechanism 1 detects a lens movement operation mechanism (not shown) capable of varying the focal length of the optical system within a range of 150 mm to 400 mm, an electric drive motor 11 for driving the same, and an operation movement amount thereof. And an encoder 12 for doing so. Further, in FIG. 1, reference numerals 2, 3, and 4 denote a pair of variable power lenses, an imaging lens, and an eyepiece lens for stereoscopic observation,
These make up a stereoscopic observation optical system in the mirror body 5. The variable power lens 2 has an electric drive mechanism (not shown) and a motor 8 for driving the same.

FIG. 2 shows the configuration of the electric system in this embodiment. In FIG. 2, reference numeral 6 denotes an operating foot switch, which is provided with a magnification changing operation switch 6a for supplying a magnification changing operation signal to a magnification changing drive circuit 7 for driving and operating the stereoscopic observation optical system. Focusing operation switch 6b and WD operation switch 6 as focusing operation means
c and these switches 6a, 6 are provided.
Each of b and 6c is a seesaw type pedal switch. The scaling operation switch 6a of the operation foot switch 6 supplies a scaling operation signal to the scaling drive circuit 7, and the focusing operation switch 6b and the WD operation switch 6c.
And supplies a focusing operation signal to the WD control circuit 10. Here, the scaling drive circuit 7 includes a drive motor 8 for electric scaling.
Motor drive means for supplying a drive signal to

Further, the objective lens drive circuit 9 supplies a drive signal to an electric drive motor 11 of the focal length variable objective lens mechanism 1 in response to an operation signal from the WD control circuit 10.
These constitute motor drive means.

The WD control circuit 10 receives signals from the foot switch 6 when the focusing operation switch 6b and the WD operation switch 6c are operated, and a comparison operation circuit 14 which will be described later, performs a WD operation. A signal or a stop signal is received, an operation signal corresponding to the signal is supplied to the objective lens drive circuit 9, and a first WD detection circuit 13 described later is supplied with
It is composed of a logic circuit such as an OR circuit which operates so as to respectively supply the WD operation signals. The first WD detection circuit 13 calculates the amount of change in the focal length due to the WD operation signal based on the WD operation signal from the WD control circuit 10 and the output signal from the encoder 12 provided in the variable focal length objective lens mechanism 1. A counter circuit (not shown) that integrates and detects the focal length signal W1 and an arithmetic circuit are provided, and the detected focal length signal W1 is supplied to the focusing range calculation circuit 15. Also,
The second WD detection circuit 20 is composed of a counter circuit (not shown) or an arithmetic circuit (not shown) for calculating the focal length L by the output signal from the encoder 12 provided in the variable focal length objective lens mechanism 1, and the detected focal length signal. W2 is supplied to the comparison operation circuit 14.

A first setting knob 17 provided on a mount for a mirror body (not shown) is a focal length setting switch for a means for varying the focal length (WD) of the variable focal length objective lens mechanism 1. Is 3 from 175mm in 25mm increments
It has a set value of 9 steps up to 75 mm, and is connected to the WD setting circuit 16 to supply a signal corresponding thereto. The WD setting circuit 16 has a memory circuit which receives the signal and supplies it to the comparison operation circuit 14 as corresponding focal length data.

Similarly, the second setting knob 18 provided on a mount (not shown) has a variable resistor for setting the focus range and is connected to the focusing range setting circuit 19. The focusing range setting circuit 19 converts the resistance value of the variable resistor and supplies it to the focusing range calculation circuit 15 as a corresponding focusing distance range signal. Focus range calculation circuit 15
Is the focal length signal W1 from the first WD detection circuit 13,
It has a calculation circuit for calculating the focus operation range from the focus distance range signal from the focus range setting circuit 19, and supplies the calculation result of this to the comparison calculation circuit 14. With these configurations, as will be described later, a part of the focal length variable range by the focal length varying means is selected as the focusing operation range.

The comparison calculation circuit 14 compares the power-on detection circuit (not shown) with the focal length signal W2 from the second WD detection circuit 20 and the focal length data from the WD setting circuit 16, and performs WD control as a WD operation signal. A first comparator circuit (not shown) supplied to the circuit 10, a focusing operation range signal from the focusing range calculation circuit 15, and a second WD detection circuit 2
It has a second comparator circuit that compares the focal length signal W2 from 0 and, if it deviates, supplies a stop signal for stopping the focusing operation signal to the WD control circuit 10.

(Operation) As shown in FIG. 3, the set focal length WD1 of the variable focal length objective lens mechanism 1 is selected to 250 mm by the setting knob 17, and a part of the range is set to the focusing operation range. Set as 18 with 50 mm (± 25
mm) is set. Therefore, when the power switch is turned on, this is detected by a power ON detection circuit (not shown) in the comparison calculation circuit 14. As a result, first, the focal length signal W2 from the second WD detection circuit 20 is output by the first comparator circuit (not shown) of the comparison operation circuit 14.
And a WD operation signal is output to the WD control circuit 10 so as to match the focal length data from the WD setting circuit 16,
The motor 11 of the variable focal length objective lens mechanism 1 is driven by the objective lens drive circuit 9, and the focal length of the variable focal length objective lens mechanism 1 is set to WD1 in FIG. At this time, the first WD detection circuit 13 detects the focal length signal W1. This focal length signal W1
And the focusing operation range signal from the focusing range setting circuit 19, the focusing operation range shown in FIG. 3 is 250 ± 25 mm.
The focal length range is set to (225 to 275 mm).

Next, by operating the focusing operation switch 6b which is the operating means of the foot switch 6, the electric focusing adjustment operation can be performed within the range of 250 mm ± 25 mm. The second WD detection circuit 20 follows the change in the focusing distance due to this focusing operation and always calculates the current focal length. The second comparator circuit (not shown) of the comparison operation circuit 14 compares the focal length signal W2 from the second WD detection circuit 20 with the focusing range signal from the focusing range calculation circuit 15, and when the range is deviated, The operation of the focusing operation is stopped.

As the operation progresses, the operation site O reaches a deep part in the body cavity with respect to the surface part P of the body cavity as shown in FIG. As a matter of course, there may be a case where the focusing operation cannot be performed as described above.
Therefore, the operator operates the WD operation switch 6c of the foot switch 6 in order to maintain the distance L between the distal end portion of the mirror body 5 and the body cavity surface portion P at the operation portion.
0 and the objective lens drive circuit 9 drive the motor 11, and the focal length variable objective lens mechanism 1 changes the focal length to 2
Suppose it is 0 mm longer. This displacement is detected by the encoder 12, and this 20 mm is detected by the first WD detection circuit 13.
Is calculated, and in the focusing range calculation circuit 15, WD2 is 27
The focusing operation range is 270 mm ± 25 mm (245 mm
Up to 295 mm). Therefore, the operator may appropriately set the focusing operation range by the WD operation switch 6c of the foot switch 6 according to the progress of the operation.

Further, the focal length detected by the second WD detection circuit 20 can be easily displayed as numerical data on the mount or the mirror body 5. The operator may be informed of the above-mentioned operation by voice.

Although the switches for the focusing operation and the WD operation which are different from each other are provided here, the operation function may be switched by a single operation switch. Further, the switch may be automatically switched to the one for WD operation when the end of the focus is reached.

(Effect) According to the first embodiment, the variable focal length objective lens has a variable focal length range of 150 mm.
Even with a wide range such as ~ 400 mm, not only can the appropriate focal length be easily set according to the surgery contents at that time, but it can also be easily changed during surgery.
By setting the focusing operation range for focus adjustment, it is possible to prevent the focal length from being extremely short and long during the operation. This focusing operation range can also be arbitrarily set according to the operation of the operator, and when the operator performs an operation using the variable focal length objective lens, the scope comes into contact with the body surface or the surgical tool. Originally, so that the mirror does not interfere with
Eliminates the need for unnecessary attention. Furthermore, since it can be carried out with a simple configuration and no special device is required, reliability of an important medical device does not deteriorate. <Second Embodiment> A second embodiment of the present invention will be described with reference to FIGS. 4 is a view of a display mode shown to the operator, FIG. 5 is an external view showing the overall configuration of the surgical microscope, FIG. 6 is a view showing the configuration of an eyepiece for display in the visual field, and FIG. 7 is displayed in the visual field. For explaining the displayed information, FIG.
FIG. 3 is a block diagram showing a configuration of an electric system.

(Structure) First, the overall structure of the surgical microscope will be described with reference to FIG. Reference numeral 220 is a pedestal having a built-in electrical system structure as shown in FIG. 8. The pedestal 220 has a first arm 221 which is rotatable around a vertical axis Oa and which has a light source (not shown) built therein. Has been done. First
At the other end of the arm 221, a second arm 222, which is a pantograph arm rotatably supported about the vertical axis Ob and rotatable about the axis Od, is supported. The second arm 222 is held in balance by a spring (not shown). At the other end of the second arm 222,
Depression arm 2 rotatably supported around vertical axis Oc
23 is supported, and the mirror body 5 is supported by the elevation arm 223 so as to be rotatable about the rotation axes Oe and Of. An operation handle 224 is attached to the mirror body 5.

Non-excitation actuated electromagnetic brakes Ma to Mf (not shown in FIG. 5) for freely adjusting and fixing the observation direction of the mirror body 3 on the rotating shafts Oa to Of in a three-dimensional manner.
Are attached to each rotating shaft. These electromagnetic brakes Ma to Mf and a mirror position adjusting switch (not shown) provided on the operation handle 224 are connected to a drive circuit 240 shown in FIG.

Regarding the structure of the optical system in the mirror body 5,
Other than the eyepiece, the same as the first embodiment described above,
The description thereof is omitted. The eyepiece for display in the visual field will be described with reference to FIGS. In the figure, 50
Is an eyepiece system for in-field display, and the lens 5
A display device 54 in which a substrate 51, a diaphragm 52, and a sheet 53 are integrated is fixed at the focal position of 8. Figure 6
As shown in (b), the display LEDs 57a,
57b is attached. LED 5 on the diaphragm 52
Openings 55a and 55b are provided corresponding to 7a and 57b, and triangular transmission patterns 56a and 56b for display are formed on the sheet 53. LEDs 57a, 57
Light from b passes through the openings 55a and 55b and illuminates the transmission patterns 56a and 56b. Board 51
LEDs 57a, 57b of the display circuit 232 shown in FIG.
It is connected to the. When the LEDs 57a and 57b selectively blink, the displays 76 and 77 in the observation visual field 78 shown in FIG. 7 blink.

Next, referring to FIG. 8, the structure of the electric system in the apparatus of this embodiment will be described. Also in this case, the same components as those in the first embodiment described above are designated by the same reference numerals, and the description thereof will be omitted. The second WD detection circuit 20 for detecting the focal length at that time by the output signal of the encoder 12 provided in the variable focal length objective lens mechanism 1.
Is connected to supply the focal length signal W2 to the comparison calculation circuit 14 and the third comparison calculation circuit 235. Same first
The focal length signal W1 obtained by integrating the change in focal length due to only the WD operation signal by the WD detection circuit 13 is supplied to the focusing range calculation circuit 15, the first comparison calculation circuit 233, and the third comparison calculation circuit 235, respectively. .

The second comparison operation circuit 234 is provided with the focal length data from the WD setting circuit 16 and the first WD detection circuit 13.
Is a circuit for comparing the focal length signal W1 from the above-mentioned, and supplying a WD stop signal for stopping the WD operation to the WD operation circuit 230. The third comparison arithmetic circuit 235 is a mirror body position (not shown) of the operation handle 224. In response to an operation signal from the adjustment switch, the operation signal is received from the drive circuit 240 that drives the electromagnetic brakes Ma to Mf to be fixed and released.
An operation detection circuit (not shown) for detecting that the lens body position adjustment operation is being performed is compared with the focal length signal W1 from the first WD detection circuit 13 and the focal length signal W2 from the second WD detection circuit 20 to focus. An AND output is obtained from a comparison circuit (not shown) that outputs an operation signal, and the output signals of the operation detection circuit and the comparison circuit, and the focusing operation signal is obtained by the WD operation circuit 2
And a logic circuit (not shown) configured to supply the voltage to the circuit 30.

The WD operation circuit 230 includes the foot switch 6
Receiving the WD operation signal and the focusing operation signal from the first comparison operation circuit 233, the WD stop signal from the first comparison operation circuit 233, the focus operation stop signal from the second comparison operation circuit 234, and the third comparison operation signal. A focusing operation signal is received from each of the circuits 235, and an operation signal is sent to the objective lens driving circuit 9 and the first WD detection circuit 13 is received.
To the WD operation signal, and to the display circuit 232 to supply the operation state signal of the variable focal length objective lens mechanism.
It is a logic circuit composed of a circuit, an AND circuit, and the like.

Further, the display circuit 232 uses the LED 57 based on the operation state signal from the WD operation circuit 230.
This is a drive circuit that drives a and 57b to turn on and blink. (Operation) Also in the second embodiment, the setting of the initial WD1 and the focusing operation range in FIG. 3 shown in the first embodiment is the same.

By using the WD operation switch of the foot switch 6, the operator can freely set WD2 within the WD variable range with respect to the initial setting of WD1 as shown in FIG. The second comparison circuit 233 compares the focal length signal W1 (that is, WD2) from the first WD detection circuit 13 with the focal length data (that is, WD1) from the WD setting circuit 16 to shorten the focal length. During operation by WD1 = W
When it becomes D2, a WD stop signal is output to the WD operation circuit 230 to stop the focal length changing operation, and the operation is stopped.

In the WD operation circuit 230, the WD stop signal from the second comparison operation circuit 233 and the WD operation signal from the foot switch 6 output a lighting signal to the display circuit in the above state to turn on the LED 57a in the display device 54. Blink,
The operator is notified by blinking the display 76 shown in FIG. 7 (see FIG. 4).

In addition, in the surgical microscope of the second embodiment, the mirror body 5 can freely select the spatial position, and the operator holds the operation handle 224 to change the observation visual field. By turning on the position adjustment switch,
The electromagnetic brakes Ma to Mf provided on the rotary shafts of the first and second arms 221, 222 and the elevation arm 223 are all released, the position of the mirror body 5 is adjusted, and the observation direction and the observation site are adjusted. It Then, when the mirror position adjusting switch is turned off, the electromagnetic brakes Ma to Mf are all fixed, and the positioning of the mirror 5 is fixed. Usually, the surgeon makes a rough focus adjustment during this positioning operation,
After this positioning, the focus is finely adjusted by the focusing operation of the foot switch 6. Now, the operator shows WD2 =
It is assumed that the lens is used at 300 mm and the focusing operation range is 300 mm ± 25 mm, and the focal length is 310 mm. The third comparison operation circuit 235 detects the lens barrel position operation period (while the electromagnetic brakes Ma to Mf are in the released state), and during that period, the focal length signal W2 = 3 from the second WD detection circuit 20.
00 mm and the focal length signal W1 from the first WD detection circuit 13
= 310 mm in the third comparison operation circuit 235, and W
WD to the WD operation circuit 230 so that 1 = W2 = 300 mm
An operation signal is output to drive the variable focal length objective lens mechanism via the objective lens drive circuit 9. At this time, WD
The WD operation signal from the third comparison operation circuit 235 is supplied to the display circuit 232 by the operation circuit 230. In the display device 54 in the eyepiece lens 50, the LED 57a is turned on to indicate that the operation is to shorten the focal length.
The operator is informed of the lit display of the display 76 shown in (1) (see FIG. 4).

During the focal length varying operation by the third comparison arithmetic circuit 235 in the direction of increasing the focal length, the display 77 shown in FIG. 7 is similarly supplied to the operator ( (See FIG. 4).

Further, in the WD operation circuit 230,
Although the comparison operation circuit 14 shown in the first embodiment allows the focusing operation only within the focusing operation range by the focusing operation stop signal, the comparison with the focusing operation signal from the foot switch 6 is made. From the stop signal from the arithmetic circuit 14, the display 76,
77 indications are supplied to the operator. If a stop signal is generated by the foot switch 6 during the operation of shortening the focal length, the display 76 is displayed. Further, in the case of an operation for increasing the focal length, the display 77 is displayed (see FIG. 4).

(Effect) With the above-described configuration, in the variable focal length objective lens mechanism 1, even when the focal length adjustment range is set, the center value of the set focusing operation range in the WD operation can be reset during the lens body position adjustment. Therefore, the intraoperative operator can perform the surgery while keeping the focal length without paying attention to the focal length. The focal length to be reset is based not only on the initial focal length but also on the focus adjustment range set according to the progress of the surgery, so there is no discomfort because it is set automatically. The reset operation is performed and the focusing operation range is secured.

Further, since the state is presented (notified) to the operator within the observation field of view when the focus operation range and the range of the WD set value of the initial setting are deviated, the burden on the operator to secure the focal length is provided. Is to lighten. Further, in the reset state, by presenting the focal length reset direction, it is possible to present to the operator the focal length state during the lens body position adjustment, which leads to improvement of operability in rough focus adjustment. <Third Embodiment> A third embodiment of the present invention will be described with reference to FIGS.
An example will be described. FIG. 9 shows the configuration of the optical system of the mirror body, FIG. 10 is a diagram illustrating the focal length state and action, and FIG. 11 is a block diagram showing the configuration of the electrical system.

(Structure) The same components as those in the first and second embodiments described above are designated by the same reference numerals, and the description thereof will be omitted. The mirror body 200 shown in FIG. 9 is supported by a supporting device including an arm, a pedestal, and the like so that spatial position adjustment and positioning fixing can be performed similarly to the second embodiment described above. The mirror body 200 is provided with the variable focal length objective lens mechanism 1 similar to that of the above-described embodiment. Mirror body 2
In 00, a pair of variable power optical systems 201 for stereoscopic observation are arranged in parallel with the observation optical axis Q (on a plane perpendicular to the paper surface). A stereoscopic observation optical system is configured by disposing an imaging lens (not shown) and an eyepiece lens 202 on each optical axis of the variable power optical system 201. In FIG. 9, only the variable magnification optical system 201 of the right side observation optical path is shown.

An active distance measuring optical system, for example, is arranged in parallel with the observation optical axis Q (a surface parallel to the paper surface). The distance measuring optical system is configured as an active type as follows. In FIG. 9, reference numeral 211 denotes a projection lens installed on the optical axis of the distance measuring optical system, and 212.
Is an index projection light source arranged at the focal position of the projection lens 211, and is an IR-LED that emits infrared light.
In the in-focus state, the surgical site O has its IR-LED 212.
It is in a position conjugate with. Further, the mirror body 200 is provided with a filter 213 that transmits only the infrared light emitted from the IR-LED 212 and reflected by the operation site O through the variable focal length objective lens mechanism 1, and the infrared light is reflected by the lens. The light is condensed by 214, is received by the CCD 215 installed at the rear focal position of the lens 214, and is photoelectrically converted. In this case, the image of the projection index by the IR-LED 212 is imaged at the center position of the CCD 215 at the time of focusing, and at the left or right position of the CCD 215 at the time of non-focusing. . That is, the IR-LED 212
And the center of the CCD 215 are arranged so as to be optically coincident with each other.

Next, the configuration of the electric system of the third embodiment will be described with reference to FIG. First, 251 receives a light emission signal from a distance measurement calculation circuit 253, which will be described later, and then IR-L
A light emitting circuit for driving the ED 212 to emit light, and 252 a CCD which also receives a light emitting signal from the distance measurement calculation circuit 253.
215 is a drive circuit which drives 215, amplifies its photoelectric conversion output, and supplies it as a position information signal to the distance measurement calculation circuit 253. 253 is a logic circuit (not shown) that outputs an emission signal by receiving an operation signal from a drive circuit 240 that performs drive control for releasing and fixing the electromagnetic brakes Ma to Mf, an AF operation signal from the foot switch 6, and the drive circuit. It is a distance measuring arithmetic circuit which is composed of an arithmetic circuit (not shown) which receives a position information signal from 252, calculates a focus position, and supplies it to the operation direction determination circuit 254.

Reference numeral 254 denotes a focusing operation range signal from the focusing range calculation circuit 15, a focal length signal W2 from the second WD detection circuit 20, a position information signal from the distance measurement calculation circuit 253, and a drive circuit 240. It is composed of a determination circuit (not shown) that receives an operation signal and performs a comparison calculation between the in-focus position and the focal length, and a logic circuit (not shown) that supplies a lighting signal to the display circuit 255 from the determination output and the operation signal. It is an operation direction determination circuit.

(Operation) Also in this third embodiment, the initial WD in FIG. 3 shown in the above-mentioned first embodiment.
1 and the setting of the focusing operation range are the same.

As shown in FIG. 10, at the beginning of surgery, the focal length may be L1 because it begins near the body surface. This L1 indicates the above-mentioned WD1. As the surgery progresses, a focal length of L2 as shown in FIG. 9 is required deep inside the body cavity, and as shown in FIG.
Set WD2 with the D operation switch. Where WD
2 = 300 mm, focusing operation range ± 25 mm (275 mm to 32
5 mm) and the focal length of the variable focal length objective lens mechanism is now 315 mm.

Here, when the operator grips the operation handle 224 to change the observation site in the operation portion O and turns on the position adjustment switch of the body to adjust the position, as shown in the second embodiment. The focal length variable objective lens mechanism 1 is driven so as to shorten the focal length by 15 mm so that L2 = WD2 (since L2 = 315 mm and WD2 = 300 mm).
At this time, a light emission signal is output from the distance measurement calculation circuit 253, the IR-LED 212 is driven to emit light, and an index is projected on the surgical site. This is received by the CCD 215 and the focus information signal calculated by the distance measurement calculation circuit 253 is output to the operation direction determination circuit 254. This operation is repeatedly performed during the operation of the position of the mirror body. The operator searches for a part to observe and roughly adjusts the focus, and displays the positional relationship between the in-focus position and the reset position WD2 in order to assist the focus. The focal position at the new observation site is focal length 2
When 90 mm is detected by the focus information signal, the operation direction determination circuit 254 compares WD2 = 300 mm and the LED 57a is driven to blink through the display circuit 255. The display of the display 76 in FIG. 7 is provided to the surgeon in a blinking state, and the scope 200 is moved to the surgical site O by the operation of adjusting the scope position.
Instruct to operate in the direction away from. On the contrary,
If the focus position is detected as 310 mm, WD2 = 3
Similarly, the display of the display 77 shown in FIG. 7 is displayed in a blinking manner by comparison with 00 mm, and an instruction is made to perform a position adjustment operation in the direction of bringing the body 200 closer to the surgical site O.

These operations are performed by the operator with the operation handle 22.
It is carried out only while the mirror position adjusting operation switch No. 4 is turned on. By this display, the operator can accurately and easily complete the focusing operation range not only when changing the observation region in the observation region changing operation but also when performing rough focus adjustment.

After this operation, it is possible to further perform the AF operation by the foot switch 6, and it is also possible to carry out the AF operation in conjunction with the operation for adjusting the position of the mirror body. Although the operation by the foot switch is shown in any of the above-described embodiments, the operation handle 224 may be a hand switch provided with operation switches for focusing, zooming, WD operation and the like.

(Effect) In the third embodiment, the focus position information is provided to the operator so that the focus can be easily adjusted even when the focal length resetting operation during the lens body position adjusting operation is also used. Therefore, it is possible to properly maintain the focal length of the variable focal length objective lens mechanism 1 and also to secure the focus adjustment range. It is possible to improve the operability in the observation site changing operation and also reduce the required time. [Additional Notes] According to the above description, the following items can be obtained. 1. In a focusing device for a surgical microscope with automatic adjustment of the focal length, an optical system with a variable focal length consisting of multiple lenses and a focal point that operates this optical system to change the focal length within the variable focal length range One of a distance varying means, a detecting means for detecting a focal length adjusting operation of the optical system by the focal length varying means and calculating a focal length thereof, and a focal length varying range by the focal length varying means. A range selecting means for selecting a range of a part as a focusing operation range, an operating means for performing a focal length variable operation effective in the focusing operation range selected by the range selecting means, and a focal length by the detecting means. Control means for comparing the focus operation range by the range selecting means, determining that the focus operation range is within the variable range of the focal length, and restricting the focusing operation. Surgical microscope for focusing device, characterized in that the. According to this, in particular, the focal length by the detecting means and the focus operating range by the range selecting means are compared and calculated, it is determined that the focus operating range is within the variable range of the focal length, and the focusing operation is restricted. Therefore, the focusing operation range does not deviate from the variable focal length range of the optical system. 2. In a surgical microscope focusing device having an optical system composed of a plurality of lenses and a focal length varying means capable of adjusting the focal length by moving at least a part of the optical system, the movement of the optical system is detected. Detection means for calculating the focal length, range selecting means for selecting a partial range of the focal length variable range by the focal length varying means, and first effective focal length range by the range selecting means Operating means, second operating means for changing the focal length range by the range selecting means, and a change in focal length by the second operating means are calculated, and the focal length range by the range selecting means is changed. Focal length range changing means to
An operating microscope focusing apparatus comprising: a control unit for performing a comparative calculation of the focal length by the detecting unit and the range selecting unit or the focal length range by the focal length range changing unit.

According to this, in the variable focal length objective lens mechanism, a part of the variable range of the focal length is set as the focusing operation range, and operating means for that is provided, and
The focal length is detected and compared with the focusing operation range, so that the focusing operation range is not deviated.
Further, operating means for moving the entire focusing operation range is provided, and the operation amount by the operating means is detected to move the focusing operation range. 3. An optical system composed of a plurality of lenses; a focal length changing means capable of adjusting a focal length by moving at least a part of the optical system; a focus position detecting means for detecting a focus position of the optical system; In a surgical microscope focusing device having a moving means for changing the position and observation direction of a mirror body containing an optical system, a detecting means for detecting the movement of the optical system and calculating a focal length, and the focus. Range selecting means for selecting a part of the focal length variable range by the distance varying means, first operating means effective in the focal length range by the range selecting means, and focal length by the range selecting means Second operation means for changing the range, focal length range changing means for calculating a change in focal length by the second operation means, and changing the focal length range by the range selecting means, and the movement. The operation of the step is detected, and the focal length is adjusted based on the detected value so that the focal length is returned to the specific value of the focal length range by the focal length range changing means, and the focal length by the in-focus position detecting means. And a control means for performing a comparison calculation with. According to this, in the variable focal length objective lens mechanism, a part of the variable range of the focal length is set as the focusing operation range, and an operating means for that is provided, and the focal length is detected to detect the focusing operation range. By making a comparison between (1) and (2), the focus operation range is not deviated. Further, in the operation of changing the observation site and the observation direction, the specific value of the focusing operation range set at that time is compared with the focal length, and the variable focal length objective lens mechanism is set so that the focal length matches the specific value. While driving it, we also compare with the focus position by the focus detection means,
Detect their correlation. 4. In a surgical microscope including a focal length variable objective lens mechanism including an optical system composed of a plurality of lenses and an electric drive mechanism for varying the focal length by moving the optical system, the movement of the optical system is detected, and The detecting means for calculating the focal length by the variable focal length objective lens mechanism, the setting means for selecting a part of the variable range of the focal length by the variable focal length objective lens mechanism, and the focal length range by the setting means The effective first operating means, the second operating means for changing the focal length range by the setting means, and the focal length change by the second operating means, and the focal length by the setting means is calculated. Calculating means for changing the range, and control means for comparing and calculating the focal length by the detecting means and the focal length range by the setting means or the calculating means. Surgical microscope and having. 5. A focal length variable objective lens mechanism including an optical system including a plurality of lenses and an electric drive mechanism for moving the optical system to vary the focal length, and a mirror body including a focus position detecting unit, and the mirror body. And a moving mechanism for changing the observation direction, the detecting means for detecting the movement of the optical system and calculating the focal length by the variable focal length objective lens mechanism, and the variable focal length objective lens. Setting means for selecting a part of the focal length variable range by the mechanism, first operating means effective in the focal length range by the setting means, and changing operation of the focal length range by the setting means Second operation means of
Computing means for calculating a change in focal length by the second operating means and changing the focal length range by the setting means;
The operation of the moving mechanism is detected, and in accordance with the detection, the focal length is adjusted so that the focal length is returned to the specific value of the focal length range by the calculating means, and the comparison calculation with the focal length by the focusing position detecting means is performed. And a control means for controlling the surgical microscope. 6. The first and second operating means are one operating means,
The surgical microscope according to any one of items 2 and 3, comprising an operation function selecting means for switching the operation function.

[0049]

As described above, according to the present invention, in the focal length varying means, a part of the focal length varying range is set as the focusing operation range, so that another focusing device for moving the mirror body or the like can be provided. Without provision, it is possible to avoid a situation where the focal length becomes extremely short during the operation, and it is possible to operate without feeling discomfort even compared with the conventional focusing device. Further, since it is not necessary to provide another focusing device, the size and weight can be reduced, and the operator's operation space in the vicinity of the mirror can be more secured.
Furthermore, since it can be simply constructed, the focusing device for the surgical microscope can be provided at low cost.

[Brief description of drawings]

FIG. 1 is an explanatory view schematically showing a configuration of a mirror body portion of a surgical microscope according to a first embodiment of the present invention.

FIG. 2 is a circuit diagram similarly showing a block diagram of a configuration of an electric system of the surgical microscope according to the first embodiment of the present invention.

FIG. 3 is likewise an explanatory view of the operation of the focusing device in the surgical microscope according to the first embodiment of the present invention.

FIG. 4 is an explanatory view showing a display mode supplied to an operator in the surgical microscope according to the second embodiment of the present invention.

FIG. 5 is an explanatory view schematically showing an entire surgical microscope according to a second embodiment of the present invention.

FIG. 6 is a perspective view showing a structure of an eyepiece for displaying in a visual field in a surgical microscope according to a second embodiment of the present invention.

FIG. 7 is an explanatory view of a display displayed in the field of view of the surgical microscope according to the second embodiment of the present invention.

FIG. 8 is a circuit diagram similarly showing a block diagram of a configuration of an electric system of the surgical microscope according to the first embodiment of the present invention.

FIG. 9 is an explanatory view schematically showing a configuration of a mirror body portion of a surgical microscope according to a third embodiment of the present invention.

FIG. 10 is an explanatory view of the action of the focusing device in the surgical microscope according to the third embodiment of the present invention.

FIG. 11 is a circuit diagram similarly showing a block diagram of a configuration of an electric system of a surgical microscope according to a third embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Focal length variable objective lens mechanism, 5 ... Mirror body, 6 ... Foot switch, 10 ... WD control circuit, 11 ... Electric drive motor, 12 ... Encoder, 13 ... 1st WD detection circuit, 1
4 ... Comparison arithmetic circuit, 15 ... Focusing range calculation circuit, 16 ... W
D setting circuit, 17 ... 1st setting knob, 18 ... 2nd setting knob, 19 ... Focus range setting circuit, 20 ... 2nd WD detection circuit.

Claims (1)

[Claims] 1. A focusing device for a surgical microscope, wherein the focal length is automatically adjusted, and a variable focal length optical system comprising a plurality of lenses, and the focal length is variable by operating this optical system. A focal length varying means for changing the range, a detecting means for detecting an adjusting operation of the focal length of the optical system by the focal length varying means and calculating a focal length thereof, and a varying focal length by the focal length varying means. A range selecting means for selecting a part of the range as a focusing operation range, and an operating means for performing an effective focal length variable operation in the focusing operation range selected by the range selecting means are provided. A focusing device for a surgical microscope.