JP2002165756A - Wireless electronic endoscopic apparatus, and scope and image signal processing unit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a means for improving an operability by enlarging a range of manual operation of an electronic scope. SOLUTION: Image signals read out from a CCD image sensor 102 are inputted in a luminance adjustment circuit 135 and a modulation circuit 136 through a buffer amp 132, delayed circuit 133 and S/H circuit 134. A difference between a luminance information extracted from an image signal in the luminance adjustment circuit 135 and a prescribed luminance is calculated, thus solving the difference by operating a driving electric current of white LED 111. An image signal is modulated to an FM signal through the modulation circuit 136, and a signal element is generated to indicate the time to drive and cease the white LED 111 based on the modulated FM signal. Output signals through the luminance adjustment circuit 135 and an emission time control circuit 137 are synthesized before outputting them to the white LED 111 through the LED drive circuit 138. A part of an exit light from the white LED 111 is led to a communication window by a light guide 120 and radiated to the outside through an optical filter 140 which transmits either red light or infrared rays alone.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a wireless electronic endoscope apparatus for transmitting an image signal without connecting an imaging section and an image signal processing section with a cable.

[0002]

2. Description of the Related Art Conventionally, an electronic endoscope apparatus has a solid-state image pickup device such as a CCD at a distal end thereof, an electronic scope inserted into a body cavity, and a light source unit for supplying illumination light to an object to be observed. And an image signal processing unit that performs a predetermined process on the image signal photoelectrically converted by the solid-state imaging device. The image signal processed by the image signal processing unit is reproduced on a TV monitor or the like connected to the image signal processing unit. The electronic scope has a flexible conduit, and an electric cable for transmitting an image signal from the solid-state image sensor to the image signal processing unit, and an illumination light supplied from a light source unit of the image signal processing unit to guide the light to the tip. Light guide is provided. That is, when observing the object to be observed, the electronic scope is operated while being constantly connected to the image signal processing unit. As a result, the operation range of the electronic scope is limited, and this is a factor that reduces the operability in the procedure.

[0003] As a solution to the poor operability of the electronic scope, for example, Japanese Patent Application Laid-Open No. 06-335450 is disclosed.
Japanese Patent Application Laid-Open Publication No. H11-163873 discloses a wireless electronic endoscope apparatus that transmits an image signal without directly connecting a scope and a processor. In this electronic endoscope device,
The image signal from the scope to the processor is transmitted by infrared communication.

[0004]

However, in the electronic endoscope apparatus disclosed in the publication, an IR modulation circuit for modulating an image signal to a frequency suitable for infrared transmission and an IR endoscope including a transmission-only infrared light emitting element are provided on the scope side. A transmitter must be provided, an IR receiver and an IR demodulator circuit must be provided on the processor side, and a special light source must be provided. As a result, there is a problem that the number of parts increases and the manufacturing cost of the electronic endoscope device, especially the scope, increases.

[0005]

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and includes a light source having a semiconductor light emitting device for irradiating an object to be observed, a solid-state image pickup device for imaging, and a solid-state image pickup device. A modulating means for modulating an image signal output from the imaging element, and a transmitting means for driving a light source irradiating the object under observation based on the signal modulated by the modulating means, and transmitting the emitted light to the outside as an optical signal And an image signal processing unit having a demodulating means for demodulating the optical signal into an image signal.

Preferably, the modulating means frequency-modulates the image signal, and more preferably, the frequency of the frequency modulation by the modulating means is higher than the driving frequency of the solid-state imaging device.

[0007] The semiconductor light emitting element emits white light, and the transmitting means transmits the emitted light of the semiconductor light emitting element to the outside via an optical filter that transmits at least one of red light and infrared light.

[0008] The light source is optionally disposed, for example, at the distal end of the scope, and is also disposed on the operation unit of the scope.

Further, a wireless electronic endoscope apparatus according to the present invention comprises a semiconductor light emitting element, a solid state imaging element for imaging, a modulating means for modulating an image signal output from the solid state imaging element, and a modulating means. Light source driving means for driving the semiconductor light emitting element based on the modulated signal; irradiation means for irradiating the object to be observed with the light emitted from the semiconductor light emitting element driven by the light source driving means; It is characterized by comprising a scope having a transmitting means for transmitting, a receiving means for receiving an optical signal, and an image signal processing unit having a demodulating means for demodulating the optical signal into an image signal.

[0010] The scope of the wireless electronic endoscope apparatus according to the present invention includes a solid-state imaging device for imaging, a light source including a semiconductor light emitting device for irradiating an object to be observed, and
Modulating means for modulating an output signal of the solid-state imaging device; and transmitting means for driving a light source that is irradiating the object under observation based on the signal modulated by the modulating means, and transmitting output light of the light source to the outside. It is characterized by.

Further, the image signal processing unit of the wireless electronic endoscope apparatus according to the present invention is a solid-state image sensor which is transmitted from a scope having a light source for irradiating an object to be observed and a solid-state image pickup means for image pickup. It is characterized by comprising receiving means for receiving an optical signal obtained by modulating a light source irradiating an object under observation based on an output signal of an imaging element, and demodulating means for demodulating the optical signal.

As described above, according to the present invention, it is not necessary to connect the scope to the image signal processing unit by a cable in order to transmit the image signal obtained from the solid-state image sensor of the scope. Therefore, the operation range of the scope in the procedure is not limited, and the operability is improved.

The illumination light irradiating the subject is also used as an optical signal for transmitting an image signal to the image signal processing unit.
Therefore, there is no need to provide a dedicated illumination means for transmission, which is economical.

In frequency-modulating an image signal, the frequency band is set higher than the driving frequency of the solid-state image sensor. Therefore, even if the illumination light is modulated, a visual defect such as flicker does not occur.

Further, by arranging the light source unit on the operation section of the scope, it becomes possible to arrange a large number of semiconductor light emitting elements, and the amount of illumination light can be increased. Therefore, a better reproduced image can be obtained on the TV monitor.

By transmitting outgoing light of the semiconductor light emitting element to the outside through a filter that transmits only infrared light,
A good communication state can be secured with the receiving means of the image signal processing unit without being affected by external light.

[0017]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram of an electronic endoscope apparatus to which the first embodiment according to the present invention is applied. An imaging sensor 100 is provided at the distal end 11 of the scope 10. An image sensor 100 includes an objective optical system 101 and a CCD image sensor 102 having a color chip filter.
Is provided. An optical image of the object to be observed is formed on the imaging area of the CCD image sensor 102 via the objective optical system 101. Further, a light source unit 110 is provided near the imaging sensor 100 at the distal end portion 11. Light source unit 1
Reference numeral 10 denotes a plurality of white LEDs (Light Em
Itting Diode) Light source consisting of 111 and each white LED 1
A light distribution optical system 112 for guiding the outgoing light of 11 to the object to be observed is provided. Although three white LEDs 111 are shown in FIG. 1, the present invention is not limited to this, and as many white LEDs 111 as the space of the distal end portion 11 allows are provided.

The distal end 11 is connected to the operating unit 1 via a flexible tube 12.
3 is connected. When the power is turned on by pressing a power button (not shown) of the operation unit 13, current is supplied to each circuit described later. An image signal is read from the CCD image sensor 102 by the CCD drive circuit 131 based on the CCD read pulse output from the timing pulse generation circuit 130 of the operation unit 13. The image signal read from the CCD image 102 is transmitted to the flexible tube 12
Is input to the buffer amplifier 132 of the operation unit 13 via the electric cable disposed in the operation unit 13. The image signal is amplified by a buffer amplifier 132, input to a delay circuit 133, subjected to the above-described delay processing associated with the pulse driving of the CCD drive circuit 131, and input to a sample and hold (S / H) circuit 134. Is done.

The image signal held at a predetermined level by the S / H circuit 134 is supplied to a luminance adjustment circuit 135 and a modulation circuit 13.
6 is input. In the luminance adjustment circuit 135, luminance information is extracted from the image signal, and a difference from a predetermined reference luminance value is calculated. Further, a drive current value of the white LED 111 is calculated and output in order to adjust the light amount of the light source unit 110 so as to eliminate the difference. On the other hand, the modulation circuit 136
Then, the input image signal is frequency-modulated (FM-modulated) and input to the light emission time control circuit 137. The frequency band in which the image signal is FM-modulated in the modulation circuit 136 is about 20 MHz (megahertz) to 50 MHz, which is set higher than the driving frequency of the normal CCD driving circuit 131. In the light emission time control circuit 137, the drive time and stop time of the white LED 111 based on the FM modulation signal,
That is, a signal component representing the blinking interval is generated.

The output signal of the luminance adjustment circuit 135 and the output signal of the light emission time control circuit 137 are combined and input to the LED drive circuit 138. The drive signal is the LED drive circuit 138
Is subjected to predetermined power amplification, and is output to the white LED 111.

As described above, in the drive signal of the white LED 111, the current component for determining the light amount is such that the luminance of the optical observation object image formed on the image pickup area of the CCD image sensor 102 matches the predetermined reference luminance value. The time component for adjusting the blinking interval is determined based on the FM modulation signal of the image signal photoelectrically converted from the optical observation object image by the CCD image sensor 102. Therefore, the illumination light applied to the object to be observed includes a frequency component based on the above-described FM modulation signal at the same time as the light amount is adjusted.

A part of the light emitted from the plurality of white LEDs 111 is guided to a communication window 139 for optical communication provided in the operation unit 13 by a light guide 120 provided in the flexible tube 12. The communication window 139 is provided with an optical filter 140 that transmits only red light or infrared light. Therefore,
Only the red light component or the infrared component included in the light emitted from the white LED 111 is emitted from the communication window 139 to the outside.
The illumination light emitted from the white LED 111 includes the above-described FM.
A frequency component based on the modulation signal is included. In other words, the optical signal radiated from the communication window 139 is a carrier signal on which the image signal of the observed object image is superimposed.

A communication window (not shown) for optical communication is provided on a part of the side surface of the electronic endoscope processor (image signal processing unit) 20. A photodiode 21 is provided near the communication window, and receives an optical signal emitted from the transmission window of the scope 10. The optical signal received by the photodiode 21 is converted into an FM signal by a receiving circuit 22 and then demodulated into an image signal by a demodulating circuit 23.

The demodulated image signal is output to a timing pulse separation circuit 24,
At 4, the horizontal synchronizing signal, the vertical synchronizing signal, etc. are separated,
It is input to the synchronization generation circuit 26.

The demodulated image signal is subjected to processes such as sampling, clamping, blanking, and amplification.
A luminance signal (Y) and a chrominance signal (RY, BY) are created and subjected to predetermined image processing such as gamma correction, and then input to an analog / digital (A / D) converter 25. You. The luminance signal and the color difference signal are converted into digital signals by the A / D converter 25 and stored in the image memory 28 via the image signal processing circuit 27.

The digitized luminance signal and color difference signal are
Read from the image memory 28 and the image signal processing circuit 27
After performing processes such as enlargement, reduction, and noise reduction, the digital / analog (D / A) converter 29 converts the signal into an analog signal. Further, character information input from a keyboard (not shown) connected to the electronic endoscope processor 20 and character information read from a card reader (not shown) are subjected to predetermined processing by the character code control circuit 30. Is output as a character signal. The analog signals of the luminance signal and the color difference signal are combined with the character signal output from the character code control circuit 30, and then encoded by the encoder 31 into a luminance signal (Y) and a color signal (C), and then the S video signal (Y / C) is generated. The S video signal is sent to an external TV monitor 40 connected to the image signal processing unit 20, to which a horizontal synchronization signal and a vertical synchronization signal are added. The TV monitor 40 displays an image on a screen based on the transmitted S-video signal.

The A / D converter 25 and the D / A converter 29
, And the addition of the horizontal synchronization signal and the vertical synchronization signal are controlled by the synchronization generation circuit 26.

FIG. 2 is a block diagram of an electronic scope of a wireless endoscope apparatus to which a second embodiment according to the present invention is applied. 2, the same elements as those in FIG. 1 are given the same numbers. The light source unit 201 of the electronic scope 200 is disposed near the communication window 231 of the operation unit 230. The light source unit 201 has a plurality of white LEDs 111 and a condenser lens 202 as in the first embodiment. A part of the light emitted from the white LED 111 is guided to the condenser lens 202 by a half mirror (not shown), and a part is guided to the communication window 231.

The outgoing light guided to the condenser lens 202 is focused on the incident end of the light guide 221 provided in the flexible tube 220. The light guide 221 extends to the distal end 210 of the flexible tube 220, and has an emission end at the light distribution optical system 20.
3 are provided. That is, the light emitted from the white LED 111 is guided to the tip of the scope 10 by the light guide 221, and is radiated to the object to be observed ahead through the light distribution optical system 203. On the other hand, the outgoing light guided to the communication window 231 is radiated outside via the infrared filter 140. Other configurations are the same as those of the first embodiment. The image information transmitted from the electronic scope 200 is received by the same image signal processing unit as in the first embodiment, and the above-described image signal processing is performed.

In the first and second embodiments, the CCD
Although FM modulation is used as a modulation method of the image signal obtained from the image sensor 102, the present invention is not limited to this. An A / D converter is provided in the operation unit of the electronic scope, and CC
The image signal obtained from the D image sensor 102 is digitized, and the digital signal is subjected to pulse code modulation (PCM).
May be.

In the first and second embodiments, the white LED 111 is used as a light source, but the present invention is not limited to this. An LED that emits red (R) light, an LED that emits green (G) light, and an LED that emits blue (B) light are appropriately disposed, and each LED emits light at the same time to achieve RGB.
The emitted light of each color may be mixed, and white light may be radiated on the object to be observed. In this case, the light of the LED that emits the R light can be directly emitted from the communication window without providing the above-described optical filter that limits the wavelength band of the transmission light. Further, at this time, only the LED that emits the R light may be modulated and driven based on the image signal.

Further, a CC having a color chip filter
Even in a plane-sequential scope using a monochrome CCD image sensor instead of the D image sensor 102, an LED that emits R light, an LED that emits G light, and B
An LED that emits light is provided at the tip or operation
It is possible to emit an optical signal while sequentially emitting B light, and to perform image processing on the optical signal received by the image signal processing unit by a plane sequential method. At this time, RGB
Each of the RGB image signals sequentially generated under the illumination light of the three field periods of each color may be transmitted collectively in the illumination period of the subsequent R field.

[0033]

As described above, according to the present invention, there is no need to connect the electronic scope and the image signal processing unit with a cable, so that the electronic scope is inserted into a body cavity to perform a procedure. Operable range is widened and operability is improved. Furthermore, according to the present invention, since the light emitting element serving as the light source for optical communication is also used as the light source for illumination, the light emitting element is not required as a special light source dedicated to optical communication, and the number of components does not increase. . Therefore, manufacturing costs can be reduced.

[Brief description of the drawings]

FIG. 1 is a block diagram of a wireless endoscope apparatus to which a first embodiment according to the present invention is applied.

FIG. 2 is a block diagram of an electronic scope of a wireless endoscope apparatus to which a second embodiment according to the present invention is applied.

[Explanation of symbols]

 10, 200 Electronic scope 11, 210 Tip 12, 220 Flexible tube 13, 230 Operation unit 20 Image signal processing unit 40 TV monitor 21 Photodiode 101 Objective optical system 102 CCD image sensor 111 White LED 112, 203 Light distribution optical system

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) G02B 23/26 G02B 23/26 Z H04N 7/18 H04N 7/18 M // H04B 10/22 H04B 9 / 00 A 10/00 (72) Inventor Hiroshi Sano 2-36-9 Maeno-cho, Itabashi-ku, Tokyo Asahi Gaku Kogyo Co., Ltd. (72) Inventor Haruhiko Hibi 2-36-9 Maeno-cho, Itabashi-ku, Tokyo Asahi Gaku Kogyo Co., Ltd. F term (reference) 2H040 BA00 CA03 CA06 CA12 CA23 DA22 GA02 GA10 GA11 4C061 CC06 GG01 JJ06 LL02 QQ06 RR04 RR14 SS13 UU05 5C054 CA05 CC02 FC11 FF02 HA12 5K002 AA01 AA03 FA03 GA01

Claims (9)

[Claims] A light source including a semiconductor light emitting element for irradiating an object to be observed; a solid-state imaging element for imaging; a modulating unit for modulating an image signal output from the solid-state imaging element; A scope having a transmitting unit that drives the light source that is irradiating the object under observation based on the signal modulated by the unit, and transmits the emitted light to the outside as an optical signal, and a receiving unit that receives the optical signal. And an image signal processing unit having demodulation means for demodulating the optical signal into an image signal. 2. The wireless electronic endoscope apparatus according to claim 1, wherein the modulation unit frequency-modulates the image signal. 3. The wireless electronic endoscope apparatus according to claim 2, wherein the frequency of the frequency modulation by the modulation unit is higher than a driving frequency of the solid-state imaging device. 4. The semiconductor light emitting device emits white light,
2. The transmission unit according to claim 1, wherein the transmitting unit transmits the outgoing light of the semiconductor light emitting element to the outside via an optical filter that transmits at least one of red light and infrared light.
A wireless electronic endoscope device according to claim 1. 5. The wireless electronic endoscope apparatus according to claim 1, wherein the light source is disposed at a distal end of the scope. 6. The wireless electronic endoscope apparatus according to claim 1, wherein the light source is disposed on an operation unit of the scope. 7. A semiconductor light emitting device, a solid state imaging device for imaging, a modulating unit for modulating an image signal output from the solid state imaging device, and the semiconductor light emitting device based on a signal modulated by the modulating unit. Light source driving means for driving the element, irradiating means for irradiating the object to be observed with light emitted from the semiconductor light emitting element driven by the light source driving means, and transmitting means for transmitting the emitted light to the outside as an optical signal A wireless electronic endoscope apparatus comprising: a scope; a receiving unit for receiving the optical signal; and an image signal processing unit having a demodulating unit for demodulating the optical signal into an image signal. 8. A solid-state imaging device for imaging, a light source composed of a semiconductor light-emitting device for irradiating an object to be observed, a modulator for modulating an output signal of the solid-state imaging device, and a modulator modulated by the modulator. And a transmitting means for driving the light source irradiating the object under observation based on the received signal and transmitting the output light of the light source to the outside. 9. The method of irradiating an object under irradiation based on an output signal of the solid-state imaging device, which is transmitted from a scope having a light source for irradiating the object to be observed and a solid-state imaging unit for imaging. An image signal processing unit for a wireless electronic endoscope device, comprising: a receiving unit that receives an optical signal obtained by modulating a light source; and a demodulating unit that demodulates the optical signal.