JP4394373B2 - Sidescope - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a side view for observing a living body positioned in the radial direction of an insertion tube, and capable of capturing a living body observation image with a built-in CCD.
[0002]
[Patent Document 1]
JP-A-11-137512
[Prior art]
It is known that there are two types of electronic endoscopes: a direct endoscope and a side endoscope. The direct endoscope has an objective optical system disposed on the end face in the longitudinal direction of the insertion tube of the endoscope, and observes (directly views) a living body positioned in the axial direction of the insertion tube. On the other hand, the side endoscope has an objective optical system arranged on the side surface of the insertion tube, and observes (side-views) a living body located in the radial direction of the insertion tube.
[0003]
A treatment instrument elevator (elevator) is installed beside the objective optical system of the side endoscope. The elevator is inserted into the treatment instrument insertion channel of the endoscope, and is used to adjust the direction in which the treatment instrument is led out from the side surface of the insertion tube. The side endoscope is used for a treatment such as inserting a stent into a duodenal papilla.
[0004]
As described above, in the side endoscope, only a living body located in the radial direction (side view direction) of the insertion tube can be observed. In other words, when a conventional endoscope such as that described in Patent Document 1 is used, a living body that is in the axial direction of the distal end of the insertion tube, that is, in the insertion direction (direct viewing direction) of the insertion tube of the endoscope. Could not be observed. Therefore, the operator of the endoscope has to insert the distal end of the insertion tube of the endoscope into the affected part without confirming the state of the insertion tube in the insertion direction. For this reason, a skillful technique is required to insert the distal end of the insertion tube of the side endoscope into the affected area.
[0005]
Therefore, it is desirable that the side endoscope also includes an objective optical system for observing a living body in a direct viewing direction as disclosed in Patent Document 1. However, in the endoscope apparatus disclosed in Patent Document 1, in order to switch the light from the direct-view objective lens and the light from the side-view objective lens and enter the solid-state image sensor, the direct-view image and the side-view image are displayed. It is impossible to observe at the same time, and the presence of the light switching mirror lengthens the side view side optical path, resulting in a thickened insertion tube tip. Furthermore, since the visual field is different between the direct viewing direction and the side viewing direction, a configuration in which the brightness of the captured image is changed between the direct viewing direction and the side viewing direction is desired. For example, a light source device that includes a first light guide that transmits illumination light that illuminates the direct viewing direction and a second light guide that transmits illumination light that illuminates the side viewing direction, and that generates illumination light is a first light guide device. In this configuration, illumination light having different brightness is incident on the first light guide and the second light guide.
[0006]
However, in order to use the endoscope having the above-described configuration, a light source device capable of making illumination light with different brightness incident on the first light guide and the second light guide is required. That is, the endoscope having the above configuration requires a dedicated light source device.
[0007]
[Problems to be solved by the invention]
In order to solve the above problems, the present invention can be connected to a conventional light source device that only allows illumination light to enter a single light guide, and can directly and directly view a direct-view image and a side-view image. An object of the present invention is to provide a side endoscope that can change the brightness of a captured image depending on the direction and the side viewing direction.
[0008]
[Means for Solving the Problems]
In order to achieve the above object, the endoscope according to the present invention includes a first imaging area and a second imaging area arranged in parallel in a first direction, and the first direction is an endoscope. A CCD installed in the endoscope insertion tube so as to be parallel to the axial direction of the endoscope insertion tube, a first objective optical system installed on the longitudinal end surface of the endoscope tip insertion tube, and a first objective Reflecting means for bending a light beam incident on the first objective optical system so that an image by the optical system is formed on the first imaging area, and a second objective installed on the side surface of the endoscope distal end insertion tube An optical system that is arranged so that a light beam incident thereon is imaged on the second imaging area, and a first objective that is arranged between the first imaging area and the first objective optical system. A first shutter capable of passing / blocking a light beam incident on the optical system, and a second objective optical system disposed between the second imaging area and the second objective optical system The second shutter capable of passing / blocking the incident light beam, and the passage / blocking operation of the light beam by the first shutter and the second shutter are controlled to control the time during which the light beam enters the first imaging area and the second imaging area. Control means for controlling.
[0009]
According to the present invention, a direct-view image is formed on the first imaging area by the first optical system, and a side-view image is formed on the second imaging area by the second optical system. Therefore, both a direct-view image and a side-view image can be captured with one CCD. In addition, according to the present invention, it is possible to control the time during which the first and second shutters pass the light beam, so that an image formed on the first imaging area and an image formed on the second imaging area are formed. The brightness of the image obtained can be set separately.
[0010]
In the endoscope of the present invention, the first imaging area and the second imaging area are arranged in parallel in the first direction, and the first direction is the axial direction of the endoscope distal end insertion tube. The CCD installed in the endoscope tip insertion tube so as to be parallel to the endoscope, the first objective optical system installed on the longitudinal end surface of the endoscope tip insertion tube, and the image by the first objective optical system A reflecting means for bending a light beam incident on the first objective optical system so as to form an image on the first imaging area; and a second objective optical system installed on a side surface of the endoscope distal end insertion tube. A light beam incident thereon is arranged so as to form an image on the second imaging area, and a first illumination light for illuminating the periphery of the first objective optical system is transmitted. A light guide, a second light guide for transmitting the second illumination light for illuminating the surroundings of the second objective optical system, and the outside of the side endoscope. An optical distributor that splits the illumination light supplied from the first light guide and makes it incident on the first light guide and the second light guide, and a light amount adjusting means for adjusting the light amounts of the first illumination light and the second illumination light; Have.
[0011]
In the above configuration, the brightness of the illumination light can be separately controlled in the direct viewing direction and the side viewing direction. Therefore, also in this configuration, the brightness of the image formed on the first imaging area and the brightness of the image formed on the second imaging area can be set separately.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 schematically shows a endoscope system according to a first embodiment of the present invention. A side-view system 500 according to this embodiment includes a side-view electronic endoscope (hereinafter referred to as a side endoscope) 100, an electronic endoscope processor 200, and a monitor 300. The side endoscope 100 includes a direct-view objective optical system 110, a side-view objective optical system 120, a light guide 130, a right-angle prism 140, a CCD unit 150, a connector unit 170, and a changeover switch 180. . Further, the connector portion 170 has a ROM 176 built therein. The electronic endoscope processor 200 includes a light source unit 220, a timing circuit 230, a first stage signal processing circuit 250, a memory 260, a scan converter 270, a rear stage signal processing circuit 280, and a system controller 290.
[0013]
The light source unit 220 generates illumination light for irradiating the living body 401 and / or 402 that is the observation target of the endoscope 100. The light source unit 220 includes a lamp 221, a condenser lens 222, a rotary filter 223, and a diaphragm 224. The lamp 221 is a white light source such as a xenon lamp. The condensing lens 222 condenses the light from the lamp 221 at the light guide base end 131 that is the incident end of the light guide 130. The rotary filter 223 is disposed between the light guide base end 131 and the condenser lens 222. The rotary filter 223 periodically switches the wavelength band of light incident on the light guide base end 131 by a so-called surface sequential method. In other words, the light source unit 220 switches the red light (R), the green light (G), and the blue light (B) to enter the light guide base end 131 at predetermined intervals. Note that the cycle at which the light source unit 220 switches the wavelength band of light is controlled by the timing circuit 230.
[0014]
The illumination light is incident on the light guide base end 131 of the light guide 130 via the stop 224. The stop controls the amount of illumination light incident on the light guide base end 133. The aperture of the diaphragm 224 is set by the system controller 290.
[0015]
The illumination light incident on the light guide base end 131 passes through the light guide 130 and the side view side branch 130a and the direct view side branch 130b on the distal end side of the endoscope 100, and passes through the side guide side distal end 132 of the light guide 130. And is emitted from the direct-view side distal end 133. The direct view distal end 133 of the light guide 130 is disposed on the longitudinal end surface of the insertion tube tip 161 of the insertion tube 160 of the side endoscope 100. Therefore, the living body 401 in the vicinity of the longitudinal end surface of the insertion tube tip 161 is irradiated with illumination light. Further, the side view distal end 132 of the light guide 130 is disposed on the side surface of the insertion tube tip 161 of the insertion tube 160 of the endoscope 100. Therefore, the living body 402 near the side surface of the insertion tube tip 161 is irradiated with illumination light.
[0016]
The CCD unit 150 has a CCD light receiving surface 151. The CCD light receiving surface 151 is a substantially rectangular member. The CCD unit 150 is fixed in the insertion tube tip 161 so that the longitudinal direction of the CCD light receiving surface 151 is substantially parallel to the axial direction of the insertion tube 160. In addition, a first imaging area 151a is defined on the distal end side of the insertion tube of the CCD light receiving surface 151, and a second imaging area 151b is defined on the proximal end side of the insertion tube of the CCD light receiving surface 151.
[0017]
The image of the living body 401 is captured by the direct-view objective optical system 110, the right-angle prism 140, and the CCD unit 150. The light beam incident on the direct-view objective optical system 110 travels toward the right-angle prism 140, where it is bent 90 degrees and forms an image on the first imaging area 151a.
[0018]
The image of the living body 402 is captured by the side-view objective optical system 120 and the CCD unit 150. The light beam incident on the side-view objective optical system 120 forms an image on the second imaging area 151b.
[0019]
A driver circuit 171 (described later) disposed in the connector unit 170 of the side endoscope 100 transmits a control pulse to the CCD unit 150, whereby the timing at which the imaging is performed is controlled. The timing circuit 230 controls the timing of control pulse transmission by the driver circuit 171. That is, the timing of imaging by the CCD unit 150 is controlled by the timing circuit 230. An imaging method using the CCD unit 150 will be described later.
[0020]
The image signal of the captured video is sent from the CCD unit 150 to the first stage signal processing circuit 250. In the present embodiment, an image of one field is captured while a single type of illumination light is being emitted. That is, from the CCD unit 150, an image signal when a living body irradiated with red light is imaged, an image signal when a living body irradiated with green light is imaged, and a living body irradiated with blue light are imaged. The image signal of the hour is output in order.
[0021]
The first stage signal processing circuit 250 converts the image signal from the CCD unit 150 into digital image data. The digital image data converted by the first stage signal processing circuit 250 is sent to the memory 260.
[0022]
The memory 260 includes a first area 261 and a second area 262. The first region 261 includes a first R plane 261R, a first G plane 261G, and a first B plane 261B. Similarly, the second region 262 includes a second R plane 262R, a second G plane 262G, and a second B plane 262B.
[0023]
When the electronic endoscope is connected to the endoscope processor 200, the system controller 290 of the endoscope processor 200 reads the contents of the ROM 176. The ROM 176 stores the specifications of the electronic endoscope. The system controller 290 determines from the contents of the ROM 176 whether the connected electronic endoscope is the side endoscope 100 of the present embodiment.
[0024]
If the electronic endoscope connected to the endoscope processor 200 is the side endoscope 100 of the present embodiment, the first stage signal processing circuit 250 is irradiated when the image signal from the CCD unit 150 is captured. The type of illumination light and the image area in which the image signal was captured are determined. An image signal based on an image formed on the first imaging area 151a when irradiated with red light is digitized and stored in the first R plane 261R. An image signal based on an image formed on the first imaging area 151a when irradiated with green light is digitized and stored in the first G plane 261G. An image signal based on an image formed on the first imaging area 151a when irradiated with blue light is digitized and stored in the first B plane 261B. An image signal of an image formed on the second imaging area 151b when irradiated with red light is digitized and stored in the second R plane 262R. An image signal based on an image formed on the second imaging area 151b when illuminated with green light is digitized and stored in the second G plane 262G. An image signal based on an image formed on the second imaging area 151b when irradiated with blue light is digitized and stored in the second B plane 262B. Note that the timing circuit 230 controls the timing of each image data stored in and read from the memory 260 (described later).
[0025]
The scan converter 270 reads the image data stored in the memory 260 and generates one color image data. What image data the scan converter 270 generates depends on the setting contents of the changeover switch 180. The setting content of the switch 180 is transmitted to the timing circuit 230, and the timing circuit 230 determines what kind of image is displayed from the setting content of the switch 180, and only the direct view image, only the side view image, or the direct view image The scan converter 270 is controlled so as to generate image data including both side-view images.
[0026]
That is, when the changeover switch 180 is set to “display only direct view images”, the scan converter 270 generates color image data using only the digital image data stored in the first area 261. As a result, color image data including only an image formed on the first imaging area, that is, a direct-view image is generated. When the changeover switch 180 is set to “display only side-view image”, the scan converter 270 generates color image data using only the digital image data stored in the second area 262. As a result, color image data including only an image formed on the second imaging area, that is, a side-view image is generated. In addition, when the changeover switch 180 is set to “display direct view image and side view image”, the scan converter 270 uses both the digital image data stored in the first area 261 and the second area. To generate color image data. As a result, color image data in which the direct view image and the side view image are displayed side by side is generated.
[0027]
The color image data generated by the scan converter 270 is sent to the post-stage signal processing circuit 280. The post-stage signal processing circuit 280 converts the color image data into a video signal such as an NTSC signal and outputs it. The monitor 300 displays this video signal as a color image.
[0028]
The aperture 224 sets the aperture of the aperture to fully open. In the present embodiment, the adjustment of the brightness of the captured image when the endoscope 100 is connected to the endoscope processor 200 is performed by the endoscope 100. A method for adjusting the brightness of the captured image by the side endoscope 100 will be described later.
[0029]
Through the above process, an image captured by the CCD unit 150 of the endoscope 100 is displayed on the monitor 300. The system controller 290 outputs a predetermined control signal to the light source unit 220, the timing circuit 230, the first stage signal processing circuit 250, the scan converter 270, and the subsequent stage signal processing circuit 280 to perform control other than timing.
[0030]
On the other hand, if the system controller 290 determines that the electronic endoscope connected to the endoscope processor 200 is not the side endoscope 100 of the present embodiment, the first-stage signal processing circuit 250 receives the signal from the CCD unit 150. The type of illumination light irradiated when the image signal is imaged is determined. The image signal when irradiated with red light is digitized and stored in the first R plane 261R. The image signal when illuminated with green light is digitized and stored in the first G plane 261G. The image signal when irradiated with blue light is digitized and stored in the first B plane 261B.
[0031]
The scan converter 270 reads the image data stored in the memory 260 and generates one color image data.
[0032]
The color image data generated by the scan converter 270 is sent to the post-stage signal processing circuit 280. The post-stage signal processing circuit 280 converts the color image data into a video signal such as an NTSC signal and outputs it. The monitor 300 displays this video signal as a color image.
[0033]
When an electronic endoscope different from the endoscope 100 of the present embodiment is connected to the endoscope processor 200, the diaphragm 224 uses the luminance output result from the first stage signal processing circuit 250, The aperture is set so that the brightness of the color image is appropriate.
[0034]
By the above process, even when an electronic endoscope different from the endoscope 100 of the present embodiment is connected to the endoscope processor 200, the image is captured by the CCD unit of the electronic endoscope. The video is displayed on the monitor 300.
[0035]
The structure of the CCD unit 150 of this embodiment is shown in FIG. The CCD unit 150 of the present embodiment uses a full frame type CCD. The CCD unit 150 of this embodiment includes a light receiving surface 151, a horizontal CCD (HCCD) 154, a first shutter unit 158a, a second shutter unit 158b, a charge detection amplifier (FDA) 156, and a first vertical transfer pulse. It has an input terminal IV1, a second vertical transfer pulse input terminal IV2, and a horizontal transfer pulse input terminal IH.
[0036]
In the first imaging area 151a of the light receiving surface 151, the first light receiving cells 152a are arranged in a grid of M rows in the vertical direction (X direction in FIG. 2) and N columns in the horizontal direction (Y direction in FIG. 2). In the second imaging area 151b, the second light receiving cells 152b are arranged in a grid of vertical M rows and horizontal N columns. The HCCD 154 is formed adjacent to one side 153a (lower end in FIG. 2) extending in the horizontal direction of the first imaging area 151a and one side 153b (lower end in FIG. 2) extending in the horizontal direction of the second imaging area 151b. Of the HCCD 154, a portion adjacent to one side 153a extending in the horizontal direction of the first imaging area 151a is defined as a first HCCD 154a. In addition, a portion of the HCCD 154 adjacent to one side 153b extending in the horizontal direction of the second imaging area 151b is defined as a second HCCD 154b.
[0037]
In the HCCD 154, 2 × N horizontal transfer cells are arranged in a line in the horizontal direction. Each of the first HCCD 154a and the second HCCD 154b includes N horizontal transfer cells. The horizontal transfer cell included in the first HCCD 154a is defined as a first horizontal transfer cell 155a, and the horizontal transfer cell included in the second HCCD 154b is defined as a second horizontal transfer cell 155b. Each of the first horizontal transfer cells 155a is adjacent to each of the first light receiving cells 152a arranged on one side 153a of the first imaging area 151a in a one-to-one relationship. Each of the second horizontal transfer cells 155b is adjacent to each of the second light receiving cells 152b arranged on one side 153b of the second imaging area 151b in a one-to-one relationship. The second horizontal transfer cell 155b adjacent to one end 157 (the right end in FIG. 2) of the second HCCD 154b is connected to the charge detection amplifier 156.
[0038]
Transfer pulses from a driver circuit 171 (described later) arranged in the connector unit 170 are transmitted to the first vertical transfer pulse input terminal IV1, the second vertical transfer pulse input terminal IV2, and the horizontal transfer pulse input terminal IH. The first vertical transfer pulse input terminal IV1 is connected to each of the first light receiving cells 152a, and the second vertical transfer pulse input terminal IV2 is connected to each of the second light receiving cells 152b. The horizontal transfer pulse input terminal IH is connected to each of the first horizontal transfer cell 155a and the second horizontal transfer cell 155b.
[0039]
In the CCD unit 150 shown in FIG. 2, when a vertical transfer pulse is sent to the first vertical transfer pulse input terminal IV1, the charge accumulated in each of the first light receiving cells 152a is transferred from the first light receiving cell 152a to the HCCD 154. It moves to the first light receiving cell 152a or the first horizontal transfer cell 155a adjacent in the vertical direction (X direction). That is, the charges accumulated in the first light receiving cells 152a arranged on one side 153a of the first light receiving cell 152a move to the first horizontal transfer cell 155a adjacent in the X direction. The other charges accumulated in the first light receiving cells 152a move to the first light receiving cells 152a adjacent in the X direction.
[0040]
When a vertical transfer pulse is sent to the second vertical transfer pulse input terminal IV2, the charge accumulated in each of the second light receiving cells 152b is in the vertical direction (X direction) from the second light receiving cell 152b toward the HCCD 154. It moves to the adjacent second light receiving cell 152b or second horizontal transfer cell 155b. That is, the charges accumulated in the second light receiving cells 152b arranged on one side 153b of the second light receiving cell 152b move to the second horizontal transfer cell 155b adjacent in the X direction. The other charges accumulated in the second light receiving cells 152b move to the second light receiving cells 152b adjacent in the X direction.
[0041]
When a horizontal transfer pulse is sent to the horizontal transfer pulse input terminal IH, the charges accumulated in each of the horizontal transfer cells 155a and 155b of the HCCD 154 are adjacent to the horizontal transfer cell and the charge detection amplifier 156 (Y direction). Move to the horizontal transfer cell or charge detection amplifier 156. That is, the charge accumulated in the horizontal transfer cell 155b at one end (right end in FIG. 2) of the HCCD 154 moves to the charge detection amplifier 156. Charges accumulated in other horizontal transfer cells move to the horizontal transfer cell.
[0042]
The charges that have moved to the charge detection amplifier 156 are converted into voltage fluctuations and sent to the first-stage signal processing circuit 250 (FIG. 1) as image signals.
[0043]
The first shutter unit 158a is disposed between the first imaging area 151a and the right-angle prism 140. The first shutter unit 158a is, for example, a liquid crystal shutter, and can block a light beam that enters the direct-view objective optical system 110 and travels toward the first imaging area 151a. That is, when the first shutter unit 158a is “open”, the light beam incident on the direct-view objective optical system 110 forms an image on the first imaging area 151a via the right-angle prism 140. On the other hand, when the first shutter unit 158a is “closed”, the first imaging area 151a is shielded, and the light beam incident on the direct-view objective optical system 110 does not enter the first imaging area 151a.
[0044]
The second shutter unit 158b is disposed between the second imaging area 151b and the side-view objective optical system 120. The second shutter unit 158b is, for example, a liquid crystal shutter, as described above, and can block the light beam that enters the side-view objective optical system 120 and travels toward the second imaging area 151b. That is, when the second shutter unit 158b is “open”, the light beam incident on the side-view objective optical system 120 forms an image on the second imaging area 151b. On the other hand, when the second shutter unit 158b is “closed”, the second imaging area 151b is shielded, and the light beam incident on the side-view objective optical system 120 does not enter the second imaging area 151b.
[0045]
FIG. 3 is a block diagram of the connector portion 170 of the side endoscope 100. As shown in FIG. The connector 170 includes a driver circuit 171, a signal distribution circuit 172, a first signal level detection circuit 173a, a second signal level detection circuit 173b, a first comparator 174a, a second comparator 174b, a first pulse width control 175a, 2 pulse width control 175b and ROM 176.
[0046]
The driver circuit 171 uses the clock sent from the timing circuit 230, the vertical transfer pulse sent to the first vertical transfer pulse input terminal IV1, the vertical transfer pulse sent to the second vertical transfer pulse input terminal IV2, and the horizontal transfer pulse A horizontal transfer pulse sent to the input terminal IH is generated.
[0047]
The image signal from the CCD unit 150 is sent to the first stage signal processing circuit 250 and the signal distribution circuit 172.
[0048]
The signal distribution circuit 172 uses the clock sent from the timing circuit 230 to divide the image signal into one based on the first imaging area 151a and one based on the second imaging area 151b. An image signal corresponding to an image formed on the first imaging area 151a is sent to the first signal level detection circuit 173a. An image signal corresponding to the image formed on the second imaging area 151b is sent to the second signal level detection circuit 173b.
[0049]
The first signal level detection circuit 173a adds the input image signal for one field, and calculates the luminance level of the image signal for one field (that is, the brightness level of the image formed on the first imaging area 151a). To detect. The time for sending the image signal for one field is determined from the clock generated by the timing circuit 230. The detected luminance level is sent to the first comparator 174a.
[0050]
The first comparator 174a compares the luminance level sent from the first signal level detection circuit 173a with the direct-view image reference level sent from the system controller 290 (FIG. 1). The comparison result is sent to the first pulse width control 175a. The direct-view image reference level is variable.
[0051]
The first pulse width control 175a generates a pulse signal having a pulse width that determines the opening time of the first shutter 158a (that is, the exposure time of the first imaging area 151a) from the comparison result sent from the first comparator 174a. To do. This open time is feedback-controlled so that the difference between the luminance direct-view image level of the image signal for one field and the reference level is reduced. As a result, the open time is set so that the luminance level of the image signal for one field becomes substantially constant. In other words, the brightness of the direct-view image can be adjusted by appropriately changing the direct-view image reference level. In the first pulse width control 175a, when the changeover switch 180 is set to “display only a direct view image” and “display a direct view image and a side view image”, the signal level becomes high only for the opening time of the first shutter. Such a pulse is generated and sent to the first shutter 158a. The first shutter 158a is “open” while the input signal level is high, and is “closed” while it is low. The timing for sending this pulse to the first shutter 158a is determined by the clock generated by the timing circuit 230. That is, this pulse is sent to the first shutter 158a at the timing when imaging for one field is started. Accordingly, when the changeover switch 180 is set to “display only side-view image”, the first pulse width control 175a does not generate a pulse signal.
[0052]
With the mechanism as described above, a pulse signal having a predetermined pulse width is continuously sent to the first shutter 158a, so that the changeover switch 180 changes to “display direct view image” and “display direct view image and side view image”. When set, the luminance level of the image signal imaged on the first imaging area 151a is kept substantially constant. When the changeover switch 180 is set to “display only side-view images”, the first imaging area 151a is optically masked by the first shutter 158a.
[0053]
The second signal level detection circuit 173b adds the input image signal for one field, and calculates the luminance level of the image signal for one field (that is, the brightness level of the image formed on the second imaging area 151b). To detect. The time for sending the image signal for one field is determined from the clock generated by the timing circuit 230. The detected luminance level is sent to the second comparator 174b.
[0054]
The second comparator 174b compares the luminance level sent from the second signal level detection circuit 173b with the side-view image reference level sent from the system controller 290 (FIG. 1). The comparison result is sent to the second pulse width control 175b. Note that the side-view image reference level is variable.
[0055]
The second pulse width control 175b generates a pulse signal having a pulse width that determines the opening time of the second shutter 158b (that is, the exposure time of the second imaging area 151b) from the comparison result sent from the second comparator 174b. To do. This open time is feedback controlled so that the difference between the luminance level of the image signal for one field and the side-view image reference level is reduced. As a result, the open time is set so that the luminance level of the image signal for one field becomes substantially constant. In other words, the brightness of the side view image can be adjusted by appropriately changing the side view image reference level. When the changeover switch 180 is set to “display only the side-view image” and “display the direct-view image and the side-view image”, the second pulse width control 175b keeps the signal level high for the open time of the second shutter. Is generated and sent to the second shutter 158b. The timing of sending this pulse to the second shutter 158b is determined by the clock generated by the timing circuit 230. That is, this pulse is sent to the second shutter 158b at the timing when imaging for one field is started. On the other hand, when the changeover switch 180 is set to “display only a direct view image”, the second pulse width control 175b does not generate a pulse signal.
[0056]
With the mechanism as described above, a pulse signal having a predetermined pulse width is continuously sent to the second shutter 158b, so that the changeover switch 180 “displays only the side view image” and “displays the direct view image and the side view image”. Is set, the luminance level of the image signal imaged on the second imaging area 151b is kept substantially constant. When the changeover switch 180 is set to “display only direct view images”, the second imaging area 151b is optically masked by the second shutter 158b.
[0057]
FIG. 4 is a time chart showing the input timing of the vertical transfer pulse and the horizontal transfer pulse when the changeover switch 180 (FIG. 1) is set to “display only a direct view image”.
[0058]
SVa is a vertical transfer pulse sent to the first vertical transfer pulse input terminal IV1. SVb is a vertical transfer pulse sent to the second vertical transfer pulse input terminal IV2. SH is a horizontal transfer pulse sent to the horizontal transfer pulse input terminal IH.
[0059]
As shown in FIG. 4, when the changeover switch 180 (FIG. 1) is set to “display only direct view image”, a pulse is sent once to the first vertical transfer pulse input terminal IV1, and then a horizontal transfer pulse is input. Send a pulse to terminal IH multiple times (2 x N times). By sending a pulse once to the first vertical transfer pulse input terminal IV1, the charge accumulated in each of the first light receiving cells 152a moves toward the first stage first HCCD 154a. Further, by sending a pulse 2 × N times to the horizontal transfer pulse input terminal IH, all the charges accumulated in the HCCD 154 are sequentially sent to the charge detection amplifier 156. By sending the transfer pulse at such timing, only the image signal of the image formed on the first imaging area 151a is output from the charge detection amplifier 156.
[0060]
FIG. 5 is a time chart showing the input timing of the vertical transfer pulse and the horizontal transfer pulse when the changeover switch 180 (FIG. 1) is set to “display only side-view image”.
[0061]
As shown in FIG. 5, when the changeover switch 180 (FIG. 1) is set to “display only side-view image”, a pulse is sent once to the second vertical transfer pulse input terminal IV2, and then the horizontal transfer pulse Send pulses to input terminal IH multiple times (N times). By sending a pulse once to the second vertical transfer pulse input terminal IV2, the charge accumulated in each of the second light receiving cells 152b moves toward the first-stage second HCCD 154b. Further, by sending a pulse N times to the horizontal transfer pulse input terminal IH, all the charges accumulated in the HCCD 154 are sequentially sent to the charge detection amplifier 156. By sending the transfer pulse at such timing, only the image signal of the image formed on the second imaging area 151b is output from the charge detection amplifier 156.
[0062]
FIG. 6 is a time chart showing the input timing of the vertical transfer pulse and horizontal transfer pulse when the changeover switch 180 (FIG. 1) is set to “display direct view image and side view image”.
[0063]
As shown in FIG. 6, when the changeover switch 180 (FIG. 1) is set to “display direct view image and side view image”, the first vertical transfer pulse input terminal IV1 and the second vertical transfer pulse input terminal A pulse is sent to IV2 once, and then a pulse is sent to the horizontal transfer pulse input terminal IH multiple times (2 × N times). By sending a pulse once to the first vertical transfer pulse input terminal IV1, the charge accumulated in each of the first light receiving cells 152a moves toward the first first HCCD 154a. By sending a pulse once to the second vertical transfer pulse input terminal IV2, the charge accumulated in each of the second light receiving cells 152b moves toward the second stage second HCCD 154b. Further, by sending a pulse 2 × N times to the horizontal transfer pulse input terminal IH, all the charges accumulated in the HCCD 154 are sequentially sent to the charge detection amplifier 156. By sending the transfer pulse at such timing, both the image signal of the image formed on the first imaging area 151a and the image signal of the image formed on the second imaging area 151b are both detected by the charge detection amplifier 156. Is output from.
[0064]
7 and 8 are a perspective view and a plan view, respectively, schematically showing an imaging state on the CCD light receiving surface 151 of the CCD unit 150 of the present embodiment. FIG. 9 is a diagram schematically showing image data stored in each plane of each area of the memory 260 based on the image signal output from the CCD unit 150 of FIGS.
[0065]
As shown in FIG. 7, the light beam from the letter “F” imitating the observation target of the living body 401 is inverted left and right and up and down via the direct-view objective optical system 110 and projected onto the right-angle prism 140 where it is bent 90 degrees. Toward the first imaging area 151a, the light beam from the letter “F” imitating the observation target of the living body 402 is reversed left and right and up and down via the objective optical system 1120 for side viewing, and directed to the second imaging area 151b. As shown in FIG. 8, each light beam forms an image on the first imaging area 151a and the second imaging area 151b. The CCD unit 150 transmits image signals corresponding to these formed images to the first stage signal processing circuit 250 (FIG. 1). The first stage signal processing circuit 250 converts the transmitted image signal into digital image data and transmits it to the memory 260.
[0066]
The digital image data transmitted to the memory 260 is stored in each plane of each area of the memory 260 as shown in FIG. That is, digital image data corresponding to the image formed in the first imaging area 151a of the CCD unit 150 is stored in a predetermined plane of the first area 261 in the form shown in FIG. 9B, and the second imaging area 151b. The digital image data corresponding to the image formed on the second area 262 is stored in a predetermined plane in the second area 262 in the form shown in FIG. If the image formed in each imaging area is a normal image with respect to the charge transfer direction, the digital image data is stored in the form shown in FIG. 9A, and the address control during reading is the same as the address control during storage. Although the same, in practice, the images formed in the first imaging area 151a and the second imaging area 151b do not become normal images, so the address control during reading must be changed from the address control during storage. That is, in the case of FIG. 9B, reading is performed by changing the address in the direction of the arrow starting from the address of the lower left corner, and when reading by the address of the upper corner is completed, the line is shifted by one line in the direction of the white arrow and starts again from the lower corner. Repeat the read operation by changing the address in the direction of the arrow. In the case of FIG. 9C, reading is performed by changing the address in the direction of the arrow starting from the address in the upper left corner, and when reading by the address in the lower corner is completed, the process proceeds by one line in the direction of the white arrow and starts again in the direction of the arrow from the upper corner. Repeat the read operation with the address changed. When such a reading operation is performed on the memory 260, a normal image is displayed on the monitor 300 for both the direct-view image and the side-view image.
[0067]
As described above, according to the present embodiment, both the direct-view image and the side-view image can be captured, and the brightness of the direct-view image and the side-view image can be adjusted separately.
[0068]
In the present embodiment, the brightness of the direct-view image and the side-view image is adjusted separately by controlling the opening time of the first shutter 158a and the second shutter 158b. It is not limited to. That is, it is possible to separately control the amount of illumination light emitted from the direct view side light guide and the amount of illumination light emitted from the side view side light guide. A second embodiment of the present invention described below is a side-view system having such a configuration.
[0069]
FIG. 10 schematically shows the endoscope system according to the second embodiment of the present invention. A side endoscope system 1500 according to the present embodiment includes a side view type electronic endoscope (hereinafter referred to as a side endoscope) 1100, an electronic endoscope processor 200, and a monitor 300. The side view 1100 of the present embodiment includes a direct-view objective optical system 110, a side-view objective optical system 120, a proximal-side light guide 1300, a direct-view side light guide 1301, and a side-view side light guide 1302. It has a right-angle prism 140, a CCD unit 150, a connector portion 1170, and a changeover switch 180. The connector 1170 has a ROM 1176 built therein.
[0070]
Since the configurations of the electronic endoscope processor 200 and the monitor 300 are the same as those of the first embodiment of the present invention, the description thereof is omitted.
[0071]
In the present embodiment, the illumination light generated by the light source unit 220 is incident on the light guide base end 1303 of the base end side light guide 1300. The illumination light incident on the light guide base end 1303 passes through the base end side light guide 1300 and is directed to the direct view side light guide 1301 by the optical distributor (described later) in the connector unit 1170 and the side view side. The light is distributed to the side-viewing illumination light toward the light guide 1302. The direct viewing illumination light is radiated from the light guide distal end (direct viewing side) 1310 of the direct viewing side light guide 1301. The side viewing illumination light is emitted from the light guide distal end (side view side) 1320 of the side view side light guide 1302. The light guide distal end (direct view side) 1310 is disposed on the end surface in the longitudinal direction of the insertion tube tip 161 of the insertion tube 160 of the endoscope 1100. Therefore, the living body 401 in the vicinity of the longitudinal end surface of the insertion tube tip 161 is irradiated with illumination light. Further, the light guide distal end (side view side) 1320 is disposed on the side surface of the insertion tube tip 161 of the insertion tube 160 of the side endoscope 1100. Therefore, the living body 402 near the side surface of the insertion tube tip 161 is irradiated with illumination light.
[0072]
The configurations of the direct-view objective optical system 110, the side-view objective optical system 120, the right-angle prism 140, the CCD unit 150, the connector unit 1170, and the changeover switch 180 are the same as those in the first embodiment of the present invention. Since there is, explanation is omitted.
[0073]
FIG. 11 is a block diagram of the connector portion 1170 of the endoscope 1100. As shown in FIG. The connector unit 1170 includes a driver circuit 1171, a signal distribution circuit 1172, a first signal level detection circuit 1173a, a second signal level detection circuit 1173b, a first comparator 1174a, a second comparator 1174b, an optical distributor 1175, a first adjustment It includes an optical device 1177a, a second dimmer 1177b, a shutter control circuit 1178, and a ROM 1176. The ROM 1176 stores the same content as the ROM 176 in the first embodiment, and is read by the system controller 290 as in the first embodiment.
[0074]
The light guide tip 1304 of the base end side light guide 1300 is connected to the optical distributor 1175. The optical distributor 1175 distributes the illumination light transmitted via the proximal light guide 1300 to the first dimmer 1177a and the second dimmer 1177b.
[0075]
The driver circuit 1171 uses the clock sent from the timing circuit 230, the vertical transfer pulse signal sent to the first vertical transfer pulse input terminal IV1, the vertical transfer pulse signal sent to the second vertical transfer pulse input terminal IV2, and the horizontal A horizontal transfer pulse signal sent to the transfer pulse input terminal IH is generated.
[0076]
The image signal from the charge detection amplifier 156 of the CCD unit 150 is sent to the first stage signal processing circuit 250 and the dimming control circuit 1172.
[0077]
The signal distribution circuit 1172 uses the clock sent from the timing circuit 230 to divide the image signal into one based on the first imaging area 151a and one based on the second imaging area 151b. An image signal corresponding to an image formed on the first imaging area 151a is sent to the first signal level detection circuit 1173a. An image signal corresponding to the image formed on the second imaging area 151b is sent to the second signal level detection circuit 1173b.
[0078]
The first signal level detection circuit 1173a adds the input image signal for one field, and calculates the luminance level of the image signal for one field (that is, the brightness level of the image formed on the first imaging area 151a). To detect. The time for sending the image signal for one field is determined from the clock generated by the timing circuit 230. The detected luminance level is sent to the first comparator 1174a.
[0079]
The first comparator 1174a compares the luminance level sent from the first signal level detection circuit 1173a with the direct-view image reference level sent from the system controller 290 (FIG. 1). The comparison result is sent to the first dimmer 1177a. The direct-view image reference level is variable.
[0080]
The first dimmer 1177a is a kind of stop, and reduces the amount of illumination light sent to the first dimmer 1177a so as to enter the incident end of the direct-view-side light guide 1301. The amount of illumination light incident on the incident end of the direct view side light guide 1301 is determined by the aperture of the diaphragm. The first dimmer 1177a determines the aperture of the aperture from the comparison result sent from the first comparator 1174a. This opening degree is feedback-controlled so as to reduce the difference between the luminance level of the image signal for one field and the reference level for direct view images. As a result, the aperture of the diaphragm is set so that the luminance level of the image signal for one field becomes substantially constant.
[0081]
By controlling the aperture of the first dimmer 1177a by the mechanism as described above, the luminance level of the image signal imaged on the first imaging area 151a is kept substantially constant. In other words, the brightness of the direct-view image can be adjusted by appropriately changing the direct-view image reference level.
[0082]
The second signal level detection circuit 1173b adds the input image signal for one field, and calculates the luminance level of the image signal for one field (that is, the brightness level of the image formed on the second imaging area 151b). To detect. The time for sending the image signal for one field is determined from the clock generated by the timing circuit 230. The detected luminance level is sent to the second comparator 1174b.
[0083]
The second comparator 1174b compares the luminance level sent from the second signal level detection circuit 1173b with the side-view image reference level sent from the system controller 290 (FIG. 1). The comparison result is sent to the second dimmer 1177b. Note that the side-view image reference level is variable.
[0084]
The second dimmer 1177b is a kind of stop, and reduces the amount of illumination light sent to the second dimmer 1177b so as to be incident on the incident end of the side view side light guide 1302. The amount of illumination light incident on the incident end of the side view side light guide 1302 is determined by the aperture of the diaphragm. The second dimmer 1177b determines the aperture of the aperture from the comparison result sent from the second comparator 1174b. This opening degree is feedback-controlled so as to reduce the difference between the luminance level of the image signal for one field and the side-view image reference level. As a result, the aperture of the diaphragm is set so that the luminance level of the image signal for one field becomes substantially constant.
[0085]
By controlling the aperture of the second dimmer 1177b by the mechanism as described above, the luminance level of the image signal imaged on the second imaging area 151b is kept substantially constant. In other words, the brightness of the side view image can be adjusted by appropriately changing the side view image reference level.
[0086]
The shutter control circuit 1178 controls the first shutter 158a and the second shutter 158b according to the setting content of the changeover switch 180. That is, when the changeover switch 180 (FIG. 10) is set to “display only direct view image”, the first mask 158a (FIG. 2) is “open” and the second mask 158b is “closed”. Only the light beam incident on the direct-view objective optical system 110 forms an image on the light receiving surface 151. When the changeover switch 180 (FIG. 10) is set to “display only side-view image”, the first mask 158a (FIG. 2) is “closed”, and the second mask 158b is “open”. Only the light beam incident on the viewing objective optical system 120 forms an image on the light receiving surface 151. Further, when the changeover switch 180 (FIG. 10) is set to “display only a direct view image”, both the first mask 158a (FIG. 2) and the second mask 158b are “open”, and the direct view objective optical system 110 is set. Both the incident light beam and the light beam incident on the side-view objective optical system 120 form an image on the light receiving surface 151.
[0087]
As described above, also in this embodiment, both the direct-view image and the side-view image can be captured, and the brightness of the direct-view image and the side-view image can be adjusted separately.
[0088]
【The invention's effect】
As described above, according to the present invention, it is possible to connect to a conventional light source device in which illumination light is only incident on a single light guide, and a direct view image and a side view image can be observed at the same time, and a direct view direction. And a side endoscope in which the brightness of the captured image can be changed depending on the viewing direction.
[Brief description of the drawings]
FIG. 1 schematically shows a side view endoscope system according to a first embodiment of the present invention.
FIG. 2 is a block diagram of a CCD unit according to the first embodiment of this invention.
FIG. 3 is a block diagram of a connector unit according to the first embodiment of the present invention.
FIG. 4 is a time chart showing the input timing of a vertical transfer pulse and a horizontal transfer pulse when the changeover switch is set to “display only a direct view image” in the first embodiment of the present invention.
FIG. 5 is a time chart showing the input timing of a vertical transfer pulse and a horizontal transfer pulse when the changeover switch is set to “display only side-view image” in the first embodiment of the present invention.
FIG. 6 is a time chart showing the input timing of a vertical transfer pulse and a horizontal transfer pulse when the changeover switch is set to “display direct view image and side view image” in the first embodiment of the present invention. is there.
7 is a perspective view schematically showing an imaging state on the CCD light receiving surface 151 of the CCD unit 150 of the present embodiment. FIG.
FIG. 8 is a plan view schematically showing an imaging state on the CCD light receiving surface 151 of the CCD unit 150 of the present embodiment.
9 is a diagram schematically showing image data stored in each plane of each area of the memory 260 based on the image signal output from the CCD unit 150 of FIGS. 7 and 8. FIG.
FIG. 10 schematically shows a side view endoscope system according to a second embodiment of the present invention.
FIG. 11 is a block diagram of a connector portion according to a second embodiment of the present invention.
[Explanation of sign]
100 Sidescope
110 Objective optical system for direct viewing
120 Objective optical system for side view
130 Light Guide
140 right angle prism
150 CCD units
151 Photosensitive surface
151a First imaging area
151b Second imaging area
152a First light receiving cell
152b Second light receiving cell
154 Horizontal CCD
154a 1st HCCD
154b 2nd HCCD
155a First horizontal transfer cell
155b Second horizontal transfer cell
156 Charge detection amplifier (FDA)
158a First shutter means
158b Second shutter means
170 Connector part
171 Driver circuit
172 Signal distribution circuit
173a First signal level detection circuit
173b Second signal level detection circuit
174a First comparator
174b Second comparator
175a First pulse width control
175b Second pulse width control
176 ROM
180 selector switch
200 Processor for electronic endoscope
220 Light source unit
230 Timing Circuit
250 First stage signal processing circuit
260 memory
270 Scan Converter
280 Post-stage signal processing circuit
290 System controller
300 monitors
500 Side endoscope system
1100 Endoscope
1300 Base light guide
1301 Direct view light guide
1302 Side view light guide
1170 Connector section
1171 Driver circuit
1172 Signal distribution circuit
1173a First signal level detection circuit
1173b Second signal level detection circuit
1174a First comparator
1174b Second comparator
1175 Optical distributor
1176 ROM
1177a 1st dimmer
1177b Second dimmer
1178 Shutter control circuit
1500 lateral endoscope system
IV1 First vertical pulse input terminal
IV2 Second vertical pulse input terminal
IH Horizontal pulse input terminal

Claims (5)

An endoscope in which the first imaging area and the second imaging area are arranged in parallel in the first direction, and the first direction is parallel to the axial direction of the endoscope insertion tube. A CCD installed in the insertion tube;
A first objective optical system installed on a longitudinal end surface of the endoscope distal end insertion tube;
Reflecting means for bending a light beam incident on the first objective optical system so that an image formed by the first objective optical system is formed on the first imaging area;
A second objective optical system installed on a side surface of the endoscope distal end insertion tube, and arranged so that a light beam incident thereon is imaged on the second imaging area;
A first shutter disposed between the first imaging area and the first objective optical system and capable of passing or blocking a light beam incident on the first objective optical system;
A second shutter disposed between the second imaging area and the second objective optical system and capable of passing or blocking a light beam incident on the second objective optical system;
Control means for controlling the passage and blocking operation of the light flux by the first shutter and the second shutter, and for controlling the time during which the light flux is incident on the first imaging area and the second imaging area;
I have a,
The control means controls the incident time of the light beam to the first imaging area by the first shutter so that the luminance level of the image formed in the first imaging area approaches a predetermined first reference level. And controlling the incident time of the light beam to the second imaging area by the second shutter so that the luminance level of the image formed in the second imaging area approaches a predetermined second reference level.
A side endoscope characterized by that .   2. The side view endoscope according to claim 1, wherein the horizontal transfer CCD of the CCD is arranged on one side parallel to the first direction of the CCD. 3.   The charge accumulated in the first imaging area is moved separately by a first vertical transfer pulse, and the charge accumulated in the second imaging area is moved separately by a second vertical transfer pulse. The endoscope according to claim 1 or 2. The first imaging area and the second imaging area are arranged in parallel in the first direction, and the endoscope is so arranged that the first direction is parallel to the axial direction of the endoscope distal end insertion tube. CCD installed in the mirror tip insertion tube,
A first objective optical system installed on a longitudinal end surface of the endoscope distal end insertion tube;
Reflecting means for bending a light beam incident on the first objective optical system so that an image formed by the first objective optical system is formed on the first imaging area;
A second objective optical system installed on a side surface of the endoscope distal end insertion tube, and arranged so that a light beam incident thereon is imaged on the second imaging area;
A first shutter disposed between the first imaging area and the first objective optical system and capable of passing or blocking a light beam incident on the first objective optical system;
A second shutter disposed between the second imaging area and the second objective optical system and capable of passing or blocking a light beam incident on the second objective optical system;
Control means for controlling light beam passage and blocking operations by the first shutter and the second shutter;
A first light guide for transmitting a first illumination light for illuminating the periphery of the first objective optical system;
A second light guide for transmitting second illumination light for illuminating the periphery of the second objective optical system;
An optical distributor that splits the illumination light supplied from the outside of the endoscope and makes it incident on the first light guide and the second light guide;
A light amount adjusting means for adjusting light amounts of the first illumination light and the second illumination light;
I have a,
The light amount adjusting means adjusts the light amount of the first illumination light so that a luminance level of an image formed in the first imaging area approaches a predetermined first reference level, and is connected to the second imaging area. The amount of the second illumination light is adjusted so that the brightness level of the image that has been imaged approaches a predetermined second reference level
A side endoscope characterized by that .   The side endoscope according to claim 4, wherein the optical distributor and the light amount adjusting means are built in a connector portion of the side endoscope.

Images