DE112011100495T5 - Electronic endoscope system - Google Patents

Abstract

An electronic endoscope system includes a light source that emits light that includes at least one visible band of light; an optical filter having a transmission peak at a particular wavelength within a continuous wavelength band including at least the visible band of light and having a transmission distribution greater than zero and less than the transmission peak within the entire continuous wavelength band except for the transmission peak value; an optical filter switching means which introduces the optical filter into an illumination beam path of the light source or retracts the optical filter from the illumination beam path; a color solid-state image pickup device that receives reflected light from an object that is illuminated with illumination light that has passed through the optical filter or not passed through the optical filter; and an image forming means that generates a color image that can be displayed on a monitor by processing an image signal output from the solid state image pickup device.

Description

Technical area

The present invention relates to an electronic endoscope system for observing a color image of an object, in particular an electronic endoscope system designed to allow a user to observe the entire structure of a particular organism.

State of the art

As a system for diagnosing an internal part of a body cavity of a patient, an electronic endoscope system is well known and used in practice. Thus, an electronic endoscope is known that has a function of illuminating an object with light through a narrow band filter that transmits light with a wavelength band within which a particular organism has a high absorbance, the endoscope system being separated from the object receives a scattered light component, generates a spectral image that highlights the particular organism. However, in the electronic endoscope system of this type, the observable wavelength band is fixed. Therefore, there is a problem that a normal color image can not be obtained, and it is not possible to perform a comparative diagnosis between a normal color image and a spectral image.

For this reason, for example, proposes the provisional Japanese Patent Publication HEI1-297042A (hereinafter referred to as Patent Document 1), an electronic endoscope system which makes it possible to perform a comparative diagnosis. Specifically, the electronic endoscope system described in Patent Document 1 is configured to control the wavelength band of the illumination light by switching the bandpass filter revolver disposed in an illumination beam path and selectively generate a spectral image and a normal color image, respectively. By capturing these two images and then comparing those images, it becomes easy to understand the relationship between a particular organism and another organism; Therefore, advantages are to be expected insofar as the accuracy of a diagnosis is increased.

Summary of the invention

However, in the electronic endoscope system described in Patent Document 1, it is not possible to simultaneously observe both a spectral image and a normal color image; it is only possible to perform an observation while indirectly comparing the two images. For this reason, it is disadvantageous that the relationship between a particular organism and another organism can not always be precisely determined. Further, there is a disadvantage in that the brightness of the obtained image is small because the amount of light is greatly cut by the narrow band filter.

The present invention has been made in consideration of the circumstances described above. That is, it is an object of the present invention to provide an electronic endoscope system capable of increasing the brightness of a spectral image highlighting a particular organism to enable a user to understand the relationship between the particular organism and another organism to understand.

To solve the above-described problem, according to an embodiment of the invention, there is provided an electronic endoscope system comprising a light source emitting light including at least one visible band of light, an optical filter having a transmission peak at a particular wavelength within a continuous band of wavelengths at least the visible band of light, and having a transmission distribution which is greater than zero and less than the transmission peak value within the entire continuous wavelength band except for the transmission peak value; an optical filter switching means which introduces the optical filter into an illumination beam path of the light source or retracts the optical filter from the illumination beam path; a color solid-state image pickup device that receives reflected light from an object that is illuminated with illumination light that has passed through the optical filter or not passed through the optical filter; and an image forming means that generates a color image that can be displayed on a monitor by processing an image signal output from the solid state image pickup device.

According to the invention, when an object is illuminated via the optical filter, it is possible to produce a spectral image whose brightness is increased, and at the same time to bring a particular organism and another organism onto one and the same screen and the image on a display screen of a monitor display. By properly retracting the optical filter from the illumination beam path, it is possible to display a normal color image on the display screen. As a specific wavelength can be a wavelength which is designed for absorption by hemoglobin. For example, the wavelength designed for absorption by hemoglobin is about 400 nm or about 550 nm.

The electronic endoscope system according to an embodiment may further include an operation means that receives an input of a user. In this case, the optical filter switching means guides the optical filter according to the input from the operating means into the illuminating beam path or retracts the optical filter from the illuminating beam path.

The invention provides an electronic endoscope system capable of increasing the brightness of a spectral image highlighting the particular organism and allowing a user to recognize the relationship between the particular organism and another organism.

Brief description of the drawings

1 shows the external appearance of an electronic endoscope system according to an embodiment of the invention.

2 Fig. 10 is a block diagram showing a configuration of the electronic endoscope system according to the embodiment of the invention.

3 Fig. 10 is a graph showing a spectral characteristic of an optical filter provided in a processor according to the embodiment of the invention.

4 shows observation images obtained when illuminating an object with an optical filter and when illuminating the object without the optical filter.

5 Fig. 10 is a graph showing a spectral characteristic of an optical filter of a processor according to another embodiment.

6 Fig. 10 is a graph showing a spectral characteristic of an optical filter of a processor according to another embodiment.

7 Fig. 10 is a graph showing a spectral characteristic of an optical filter of a processor according to another embodiment.

Embodiments of the invention

Hereinafter, an electronic endoscope system according to an embodiment of the invention will be explained with reference to the accompanying drawings.

1 shows the external appearance of an electronic endoscope system 1 according to the embodiment. As in 1 shown includes the electronic endoscope system 1 an electronic observation part 100 for imaging an object. The electronic observation part 100 has a flexible tube 11 that of a flexible shell 11a is covered. To a tip of the flexible pipe 11 is a tail 12 connected, which is covered by a rigid resin housing. At a connection part of the flexible pipe 11 and the tail 12 is a bent part 14 provided, which is designed so that it can bend freely by means of a remote control (in particular by a rotary actuation of a bending knob 13 from a manual override unit 13 out with a poximal end of the flexible tube 11 connected is). This bending mechanism is a known, installed in a conventional endoscope mechanism and formed, the bending part 14 to bend by turning the bend button 13 is pulled on an operating wire. As the orientation of the tail 2 In accordance with the bending movement caused by the above-described operation, an imaging area of the electronic observation part moves 100 ,

As in 1 shown contains the electronic endoscope system 1 a processor 200 , The processor 200 forms a unit with a signal processing device, which is the electronic observation part 100 processes incoming signals, and a light source device that illuminates the interior of a body cavity that can not reach natural light. In another embodiment, the signal processing device and the light source device are provided separately from each other.

The processor 200 is with a connection part 20 provided one at a poximalen end of the electronic observation part 100 provided connection part 10 equivalent. The connection part 20 has a connection part 10 corresponding connection structure and is formed, the electronic observation part 100 electrically and visually with the processor 200 connect to.

2 FIG. 10 is a block diagram showing a configuration of the electronic endoscope system. FIG 1 shows. As in 2 shown includes the electronic endoscope system 1 a monitor 300 that has a predetermined cable with the processor 200 connected is. The display 300 is in 1 omitted for simplicity.

As in 2 shown, the processor contains 200 a system control 202 and a timing 204 , The system control 202 controls components that the electronic endoscope system 1 form. The timing 204 gives to the various, in the electronic endoscope system 1 provided circuits clock pulses, which serve the timing of the signal processing.

After activation by a lamp current igniter 206 sends a lamp 208 Light whose spectrum is mainly from a visible band of light to an infrared band of light, which is invisible (or light that includes at least one visible band of light). As a lamp 208 is a high luminance lamp, z. As a xenon lamp, a halogen lamp and a metal halide lamp suitable. That of the lamp 208 emitted illumination light is transmitted through a condenser lens 210 bundled, with its amount of light via an aperture 212 is limited to an appropriate amount.

With the aperture 212 is via a transmission mechanism (not shown), z. As an arm and a gear, a motor 214 mechanically connected. The motor 214 is for example a DC motor and is under the drive control of a driver 216 driven. To the brightness of one on the monitor 200 is adjusted to the opening of the aperture 212 through the engine 214 so changed that from the lamp 208 emitted amount of light is limited according to the opening. A reference for determining an appropriate video brightness is in response to a user at a control panel 218 changed operation to adjust the brightness. It should be noted that a light metering circuit for adjusting the brightness by controlling the driver 216 is a circuit known per se and therefore it is not explained in this description.

For the control panel 218 Different types of configurations can be used. Examples of special control panel configurations 218 include hardware buttons attached to a front surface of the processor 200 mounted, a GUI (graphical user interface) of the type of touch-sensitive screen and a combination of hardware buttons and a GUI.

The illumination light coming through the aperture 212 is kicked off by an optical filter 213 spectrally split and falls on an entrance facet of a LCB (light-transporting bundle). With the optical filter 213 is via a transmission mechanism (not shown), z. As an arm and a gear, a motor 215 to drive under the drive control of the driver 216 mechanically connected. The motor 215 leads the optical filter 213 into a beam path or pulls the optical filter 213 from the beam path, according to one of the user on the control panel 218 made switching. During a period of time in which the optical filter 213 is withdrawn from the beam path, the illumination light passes through the aperture 212 stepped directly to the entrance facet of the LCB 102 , As an engine 215 For example, a Galvanomotor or a servomotor can be used.

The entrance facet of the LCB 102 Lived light propagates under repeated total reflection through the LCB 102 out. The illumination light that passes through the LCB 102 has spread, emerges from an exit facet of the LCB 102 which is a tip of the electronic observation part 100 forms. The illumination light coming from the exit facet of the LCB 102 has leaked out, the object illuminates via a light scattering lens 104 , The light reflected from the object generates an optical image on a light-receiving surface of a solid state image pickup device 108 ,

The solid-state imaging device 108 For example, a single chip color CCD (Charge Coupled Device) image sensor is configured to accumulate charges corresponding to the amount of light of the optical image formed on pixels on the light receiving surface and to convert the optical image into an image signal corresponding to the respective colors R , G and B corresponds. The converted image signal is amplified by a preamplifier and then via a driver signal processing circuit 112 to the signal processing circuit 220 output. In another embodiment, the solid-state imaging device 108 a CMOS (complementary metal-oxide-semiconductor) image sensor.

The driver signal processing circuit 112 accesses a store 144 to and reads out information that the electronic observation part 100 clearly determined. This clearly defining information of the electronic observation part 100 includes, for example, the number of pixels and the sensitivity of the solid-state imaging device 108 , the supported rate and the model number. The driver signal processing circuit 112 gives those from the store 114 read out, uniquely determining information to the system control 202 out.

The system control 202 leads on the basis of the clearly determining information of the electronic observation part 100 Through calculations and generates control signals. The system control 202 can be configured to have a table in which the model number of the electronic observation part and the Control information suitable for the electronic observation part with the model number is assigned to each other. In this case, the system control controls 202 by referring to the control information in the allocation table, the operations and the timings of the various circuits in the processor 200 , so for the on the processor 200 connected electronic observation part a suitable process can be performed.

The timing 204 provides the clock pulses according to the system control 202 time control to the driver signal processing circuit 112 , According to the time control 214 supplied clock pulses operates and controls the solid state image pickup device 108 with a timing that is in sync with the frame rate of the processor side 200 processed video image is.

The signal processing circuit 220 is from the driver signal processing circuit 112 supplied the image signal. The image signal is subjected to various processes including clamp, knee, interpolation, AGC (auto gain control), and AD conversion, and is latched into frame memories (not shown) for respective color signals R, G, and B based on frame advance. Each cached color signal becomes at times different from the timing 204 be cleared from the image memory and converted into a video signal that meets a predetermined standard, for. NTSC (National Television Systems Committee) or PAL (Phase Alternating Line). The converted video signal is sequentially sent to the monitor 300 fed, and thereby the image of the object on the display screen of the monitor 300 displayed. Specifically, during a period of time in which the object, while the optical filter 213 is illuminated in the beam path, the spectral image is displayed, which highlights a particular organism. During a period of time in which the object while the optical filter 213 is withdrawn from the beam path is lit, the normal color image is displayed.

3 is a graph showing the spectral property of the optical filter 213 illustrated. The vertical axis of the 3 represents the normalized transmittance and the horizontal axis represents the wavelength (unit: nm). As in 3 has the spectral characteristic of the optical filter 213 Transmission maxima near 400 nm, 550 nm, and 650 nm, and at least in a range that ranges from the visible band to the infrared band (eg, 380 nm to 1000 nm) has a transmittance greater than or equal to a certain value.

The transmittance which is greater than or equal to the predetermined value in the range ranging from the visible band to the infrared band is greater than 0 and less than half of each transmission peak value. In this embodiment, by setting the transmittance of light having a wavelength other than the specific wavelength for emphasizing the particular organism to a large value, the amount of light passing through the optical filter 213 is blocked, suppressed and the brightness of the spectral image are increased, and it becomes possible to simultaneously record the image of an organism other than the specific organism. Further, by setting the transmittance to be less than half of each transmittance peak, the decrease of the detection sensitivity with respect to the specific organism can be effectively suppressed. This means that in the embodiment, it is illuminated by illuminating the object via the optical filter 213 it is possible to simultaneously bring the particular organism and another organism on one and the same screen and the spectral image, whose brightness is increased, on the display screen of the monitor 300 display.

4 (a) shows an observation image obtained when an object without the optical filter 213 is lit, and 4 (b) shows an observation image obtained when the object passes through the optical filter 213 is illuminated. The pictures after 4 (a) and 4 (b) are images of the same object (oral cavity). As in 4 (a) Shown is a mucosal structure in the oral cavity when the light is not through the optical filter 213 occurs, observed in the form of a brighter picture. Since a particular organism is not highlighted, the picture is completely dull. If the light passes through the optical filter 213 , so will, as in 4 (b) The mucosal structure in the oral cavity is observed in the form of a brighter image along with a particular organism, while the particular image is highlighted. The bands near 400 nm and 550 nm, which correspond to the transmission maxima, tend to be absorbed by hemoglobin. Therefore, the particular organism observed here is a blood vessel in the oral cavity. As the illumination light, using the optical filter 213 is sent out, is not narrow-band light, but a broadband light, various organisms can be observed according to the respective penetration depths of the wavelengths.

The above explains the embodiment of the invention. The invention is not limited to the configuration described above, but can be varied in various ways within the technical concept according to the invention. For example, the Spectral property of the optical filter 213 not on the in 3 is limited, but can be suitably set depending on an organism of an observation target. The 5 to 7 show examples of such spectral properties. In each of the 5 to 7 In each of the spectral characteristics, at least one transmission peak exists in a predetermined wavelength band, and the transmittance greater than zero and less than half of the transmission peak value is distributed over a wide band (at least over a visible band). In addition, the spectral property in 5 the transmission peak in the wavelength band (380 nm to 420 nm) suitable for absorption by hemoglobin and in the wavelength band (470 nm to 490 nm) suitable for absorption by the colon. The spectral property is therefore suitable for observing a mucosal structure and a blood vessel structure in a surface layer in the form of a bright image. The spectral property in 6 has the transmission peaks in the wavelength bands (380 nm to 420 nm and 550 nm to 560 nm) suitable for absorption by hemoglobin. Therefore, the spectral property is suitable to observe blood vessel structures in a surface layer and a deep layer together with a mucous membrane structure of an organism. The spectral property in 7 has the transmission peak in the wavelength band (550 nm to 560 nm) suitable for absorption by hemoglobin. Therefore, the spectral property is suitable to observe a blood vessel structure in a deep layer together with a mucous membrane structure of an organism in the form of a bright image.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• JP 1-297042A [0003]

Claims (2)

An electronic endoscope system comprising: a light source that emits light that includes at least one visible band of light; an optical filter having a transmission peak at a particular wavelength within a continuous wavelength band including at least the visible band of light and having a transmission distribution greater than zero and less than the transmission peak within the entire continuous wavelength band except for the transmission peak value; an optical filter switching means which introduces the optical filter into an illumination beam path of the light source or retracts the optical filter from the illumination beam path; a color solid-state image pickup device that receives reflected light from an object that is illuminated with illumination light that has passed through the optical filter or not passed through the optical filter; and an image forming means which generates a color image which can be displayed on a monitor by processing an image signal output from the solid state image pickup device. The electronic endoscope system according to claim 1, further comprising an operation means that receives an input of a user, wherein the optical filter switching means introduces the optical filter according to the input from the operating means input to the illumination beam path or retracts from the illumination beam path.

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