JP2001061765A - Image pickup method and its device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To package an image pickup device which is capable of simultaneously picking up animation images of ordinary images and fluorescent images in a narrow space. SOLUTION: Ordinary light and fluorescence are received at different timing by one photodetecting section 10 consisting of many photosensitive elements which receive light, convert the received light to signal charges and are arrayed in a matrix form. The received light quantity of the ordinary light and the received light quantity of the fluorescence are respectively converted to signal charges. The ordinary light signal charge Et formed by conversion of the received light quantity of the ordinary light is transferred via an ordinary light horizontal shift register 60 to an ordinary light reading circuit 80 for high-speed reading out. The fluorescent signal charge Ek formed by conversion of the received light quantity of the fluorescence is transferred via a fluorescence charge accumulation section 50 capable of holding the signal charges to a fluorescence reading circuit 90 for low-speed reading out through a fluorescence horizontal shift register 70.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an imaging method and an imaging method for imaging a fluorescent image emitted from a subject such as a living body by irradiation of excitation light and a normal image of the subject illuminated by ordinary illumination light. It concerns the device.

[0002]

2. Description of the Related Art Conventionally, there has been known an image pickup apparatus for simultaneously picking up an image of a living tissue illuminated with ordinary light and an image of fluorescence emitted from the living tissue by irradiation of excitation light. In such an apparatus, a light receiving unit that captures a normal image of a living tissue illuminated with normal light (hereinafter, referred to as a normal image) as a moving image, and an image of fluorescent light emitted from the living tissue by irradiation of excitation light ( A light-receiving unit that captures a fluorescent image (hereinafter, referred to as a fluorescent image) is provided exclusively for each of them, and the device uses two light-receiving units.

For example, in an electronic endoscope, a normal image of a living tissue illuminated with pulsed normal light having a period of 1/60 second is received at a distal end portion of the endoscope, and a light for a normal image is read out as a moving image. Part, and irradiates the biological tissue with pulsed excitation light at a timing different from the pulsed normal light of the 1/60 second cycle, receives a fluorescence image generated from the biological tissue by irradiation of the excitation light, A light receiving unit for a fluorescent image, which obtains a weak fluorescent image with high quality by reading out the received fluorescent image slowly over a period longer than the imaging period of the normal image (a period longer than 1/60 second); In addition, a method of capturing a moving image of a normal image and a fluorescent image simultaneously is known.

[0004]

However, when a normal image and a fluorescent image are respectively picked up by dedicated light receiving units, two light receiving units are required, and the optical system and electric system necessary for each light receiving unit are included. In addition, the mounting space of the imaging system becomes large. In particular, in the case of an apparatus or the like used in a narrow place in a living body, such as the electronic endoscope, the mounting portion provided with the two light receiving sections becomes thick, which hinders insertion into a narrow place.
In addition, in order to obtain a moving image of a normal image and a fluorescent image with one light receiving unit in order to reduce the mounting space, for example, 1
Even if the process of receiving and reading a normal image illuminated at a period of / 60 seconds as a moving image and the process of receiving and reading a fluorescent image generated by irradiation of excitation light are performed at different timings, the received fluorescent image Since the reading time is longer than the period for reading the normal image as a moving image, the process of receiving and reading the normal image of the next period before the reading process of the fluorescent image is completed, so that the fluorescent image cannot be obtained.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and is an imaging method capable of capturing a moving image of a normal image and a fluorescent image at the same time, that is, in parallel, and which can be mounted in a small space. And an apparatus.

[0006]

According to an image pickup method of the present invention, normal light and fluorescent light are differentiated by a single light receiving portion comprising a large number of photosensitive elements arranged in a matrix for receiving light and converting the light into signal charges. Received at the timing, the received light amount of normal light and the received light amount of fluorescence are converted into signal charges, respectively, and the first signal charge converted from the received light amount of normal light is converted into high-speed signal via the first horizontal shift register. Transferring to a first output circuit for reading,
Transferring the second signal charge having the converted amount of received fluorescence to a second output circuit for low-speed reading via a second horizontal shift register via a holding unit capable of holding the signal charge; It is a feature.

The image pickup apparatus according to the present invention comprises a large number of photosensitive elements arranged in a matrix for receiving normal light and fluorescent light at different timings and converting the amounts of received normal light and fluorescent light into signal charges. , A first horizontal shift register for transferring the first signal charge converted from the amount of normal light received to the first output circuit for high-speed reading, and the amount of fluorescent light received is converted. A second signal charge holding unit for holding the second signal charge, and a second horizontal shift register for transferring the signal charge of the holding unit to a second output circuit for low-speed reading. It is characterized by the following.

[0008] The second signal charge holding section may be a second signal charge storage section for storing the second signal charge.

[0009] Further, a first signal charge accumulating section for accumulating a first signal charge can be further provided between the light receiving section and the first horizontal shift register.

The first signal charges converted by the photosensitive elements in each row are transferred to a first horizontal shift register on one side of the photosensitive elements in each row of the light receiving section, and the second signal charges are transferred to the first horizontal shift register. One vertical shift register for transferring to the second signal charge storage unit can be provided. In this case, further comprising a storage unit for a first signal charge, wherein the vertical shift register transfers the first signal charge to the first horizontal shift register via the storage unit for the first signal charge. Including.

A first vertical shift register for transferring the first signal charges converted by the photosensitive elements in each column to a first horizontal shift register is provided on both sides of the photosensitive elements in each column of the light receiving section. , And a second vertical shift register for transferring the second signal charge to the second horizontal shift register, and the second vertical shift register can also serve as the second signal charge holding unit.

[0012] The low-speed reading means reading in which signal charges are read out for a longer time than the reading cycle of the high-speed reading. For example, if the read cycle of high-speed reading is 1/60 second, which is the read cycle of a moving image,
The signal charges are read out for a time longer than 60 seconds.

The holding unit may be a storage unit for storing signal charges converted by the photosensitive elements arranged in a matrix as they are, or a photosensitive unit arranged in a matrix. It may be like a vertical shift register that also serves to temporarily accumulate these signal charges by slowly transferring the signal charges converted by each column.

[0014]

According to the imaging method and apparatus of the present invention,
The first signal charge converted from the amount of received normal light is transferred to the first output circuit for high-speed reading via the first horizontal shift register, and the second signal charge converted from the amount of received fluorescent light is converted. Is transferred to a second output circuit for low-speed reading via a second horizontal shift register via a holding unit capable of holding signal charges, so that one light receiving unit can convert a normal image and a fluorescent image. Images can be taken. Because, after receiving the pulse-illuminated normal image and reading all the converted signal charges from the light-receiving unit, emptying the light-receiving unit and receiving the pulse-illuminated normal image in the next cycle, the pulse-like By receiving the fluorescent image generated by the irradiation of the excitation light and transferring the converted signal charges from the light receiving unit to the holding unit and emptying the light receiving unit, the light receiving after the next cycle of the pulse-illuminated normal image is performed. This is because it can be continued. Note that the signal charges of the fluorescent image held in the holding unit are read from the holding unit for a long time through the second horizontal shift register for a low-speed reading while the normal image is received a plurality of times. Since it is only necessary to gradually read out the image by transferring it to the second output circuit, it is possible to obtain a moving image of a normal image and a fluorescent image by one light receiving unit without disturbing an operation for obtaining a normal image as a moving image. Can be.

Therefore, the optical system and the electrical system required for mounting the light receiving section can be provided as a single set and can be accommodated in a small mounting space. In particular, the mounting space is limited like an electronic endoscope. This is effective when implemented in a device. In addition, since the same light receiving unit receives the normal light and the fluorescent light, there is no displacement between the images of the normal image and the fluorescent image, and the image quality of the fluorescent image is also read as the moving image for the fluorescent image. Unlike the case, the signal charges can be read out over a readout time suitable for imaging weak fluorescence, so that a high-quality image can be obtained.

[0016]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, specific embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a view schematically showing a first embodiment in which an image pickup apparatus for carrying out the image pickup method of the present invention is applied to an electronic endoscope.

As shown in FIG. 1, an endoscope end portion 200 has an image pickup device 100 having a light receiving section 10 for imaging a living tissue 1 in a living body, and an image of the living tissue 1 is formed on the light receiving section 10. An optical system 5 having an excitation light cut filter 4 on its front surface, a normal light emitting optical fiber 2 for illuminating the living tissue 1 with pulsed normal light (white light), and irradiating the living tissue 1 with pulsed excitation light. An excitation light emitting optical fiber 3 is provided.

The image pickup device 100 is connected to a timing control circuit 7 for controlling the light receiving timing of the image pickup device 100 and an image signal processing circuit 8 for performing signal processing of an image signal output from the image pickup device 100. 7 further includes pulsed normal light (hereinafter referred to as normal pulsed light Pt) and pulsed excitation light (hereinafter referred to as excitation pulsed light Pr).
) Is generated, and a pulse light source control unit 6 that transmits the normal pulse light Pt and the excitation pulse light Pr to the normal light emission optical fiber 2 and the excitation light emission optical fiber 3, respectively, is connected.

A display 9 is connected to the image signal processing circuit 8, and an image formed on the light receiving section 10 and subjected to signal processing by the image signal processing circuit 8 is displayed on the display 9.

FIG. 2 shows a detailed structure of the image pickup device 100. As shown in FIG. 2, a normal image Zt of the living tissue 1 illuminated by the normal pulse light Pt and a fluorescent image Zk generated from the living tissue 1 by the irradiation of the excitation pulse light Pr are received, and the light is received according to the amount of received light. On both sides of the light receiving unit 10 composed of a large number of rows of photosensitive elements for converting into and accumulating signal charges,
Two transfer gates are connected to switch off or open (permit or disable transmission of signal charge) the signal charge received and converted by the light receiving unit 10.

A normal light transfer gate 20 connected to one of the light receiving units 10 is a transfer gate for switching off or opening a normal signal charge Et, which is a signal charge of normal light converted by the light receiving unit 10, and is connected to the other. The fluorescent transfer gate 30 is connected to the light receiving section 1.
This is a transfer gate that switches between blocking and opening of the fluorescence signal charge Ek, which is the fluorescence signal charge converted by 0.

The normal light transfer gate 20 is connected to a normal light charge storage section 40 for temporarily storing the normal signal charge Et passing through the gate 20. 40, the signal charges for one line of the image sequentially output from the normal light reading circuit 8 are received.
A normal light horizontal shift register 60 for transferring to 0 is connected.

The fluorescent transfer gate 30 is connected to a fluorescent charge storage unit 50 for temporarily storing the fluorescent signal charge Ke passing through the gate 30. A fluorescent horizontal shift register 70 that receives signal charges for one line sequentially output and transfers the signal charges to a fluorescent reading circuit 90 is connected.

As described above, the image pickup device 100 outputs the normal image Zt.
When capturing an image, an image is captured in the form of a frame transfer type CCD image sensor configured by a light receiving unit 10, a normal light transfer gate 20, a normal light charge storage unit 40, a normal light horizontal shift register 60, and a normal light reading circuit 80, When capturing the fluorescent image Zk, the fluorescent image Zk is configured to be captured in the form of a frame transfer type CCD image sensor configured by a light receiving unit 10, a fluorescent transfer gate 30, a fluorescent charge accumulating unit 50, a fluorescent horizontal shift register 70, and a fluorescent reading circuit 90. ing.

The light receiving unit 10, the normal light transfer gate 20, the fluorescent transfer gate 30, the normal light charge storage unit 40, the fluorescent charge storage unit 50, the normal light horizontal shift register 60, the fluorescent horizontal shift register 70, the normal light reading The timing of operations such as transfer of signal charges in the circuit 80 and the fluorescence reading circuit 90 is controlled by the timing control circuit 7. Further, the normal light transfer gate 20 and the fluorescent transfer gate 30 are not simultaneously opened.

Next, the operation of the electronic endoscope according to the first embodiment will be described. When capturing the normal image Zt as a moving image, the time of one frame of the moving image, that is, 1/6
The living tissue 1 is illuminated with the normal pulse light Pt for several milliseconds at every 0 second period to capture a normal image, and the image of the living tissue 1 illuminated with the normal pulse light Pt is output by the optical system 5. An image is formed on the light receiving unit 10, is received, and is converted into a signal charge (normal optical signal charge Et). Normal image Z at light receiving unit 10
When receiving t, two transfer gates 2
When the irradiation of the normal pulse light Pt is completed, only the normal optical transfer gate 20 is opened, and all the normal optical signal charges Et converted by the light receiving unit 10 are simultaneously released. 20 and is transferred to the normal photocharge storage section 40, where the normal optical signal charges E
When the transfer of t is completed, the normal optical transfer gate 20 is shut off.

The normal optical signal charges Et transferred to the normal photocharge storage unit 40 are sequentially transferred from the normal photocharge storage unit 40 to the normal light horizontal shift register 60 for each scanning line of an image, and further read by the normal light reading unit. The image signal is read as an image signal by the circuit 80, converted into a standard image signal that can be displayed by the image signal processing circuit 8, and displayed on the display 9 as a moving image.

On the other hand, when capturing the fluorescent image Zk, 1
The excitation pulse light Pr is irradiated for several milliseconds at a timing that does not interfere with the normal pulse light Pt within the period of the / 60 second cycle, and the living tissue 1 irradiated with the excitation pulse light Pr is irradiated.
Is generated as a fluorescent image Zk on the light receiving unit 10 by the optical system 5 and is received and converted into signal charges (fluorescent signal charges Ek). When the light receiving unit 10 is receiving the fluorescent image Zk, the two transfer gates 20 and 30 are shut off, and when the irradiation of the excitation pulse light Pr is completed, the fluorescent transfer gate 30 is opened and the light receiving unit 10 All the converted fluorescent signal charges Ek pass through the fluorescent transfer gate 30 at the same time and are transferred to the fluorescent charge storage unit 50. When the transfer of the fluorescent signal charge Ek is completed, the fluorescent transfer gate 30 is shut off.

The fluorescent signal charge Ek transferred to the fluorescent charge storage section 50 is transferred to the fluorescent horizontal shift register 70 sequentially for each scanning line of the image.
Is read as an image signal, converted into a standard image signal that can be displayed by the image signal processing circuit 8, and displayed on the display 9 simultaneously with the moving image of the normal image Zt.

Since the excitation light cut filter 4 is incorporated in the optical system 5 for forming the image of the living tissue 1 on the light receiving unit 10, the excitation pulse light Pr is cut off before reaching the light receiving unit 10. Only the fluorescence generated from the living tissue 1 reaches the light receiving unit 10.

Next, the details of the timing regarding the imaging of the normal image Zt and the fluorescent image Zk will be described.

The imaging of the normal image Zt is performed as follows. As shown in the timing chart of FIG. 3, the illumination of the normal pulse light Pt (1) in the cycle S1 is performed for several milliseconds during the time of one frame of the moving image, that is, the first half of the 1/60 second cycle (FIG. )), The normal image Zt (1) of the living tissue 1 formed on the light receiving unit 10 by the illumination is converted into the normal optical signal charge Et (1) by the light receiving unit 10. Next, the normal optical transfer gate 20 is opened,
All the ordinary optical signal charges Et (1) of the light receiving unit 10 are simultaneously transferred and accumulated in the ordinary photocharge accumulation unit 40 (FIG. 3).
(B)). When the signal charge of the light receiving unit 10 becomes empty, the normal optical transfer gate 20 is shut off, and the light receiving unit 1 is again turned off.
At 0, light can be received. At this point, a period of T1 is left before the next period S2 of capturing the normal image starts. The normal optical signal charges Et (1) stored in the normal light charge storage unit 40 are sequentially transferred to the normal light horizontal shift register 60 for each scanning line of an image, and further read from the normal light horizontal shift register 60 by normal light reading. Circuit 8
0 is read as an image signal.

In the process of reading the ordinary optical signal charge Et from the ordinary photocharge storage unit 40, the transfer of the ordinary optical signal charge Et (1) to the ordinary photocharge storage unit 40 is completed during the period T2, that is, in the cycle S1. Then, after the normal optical transfer gate 20 is shut off, the normal optical transfer gate 20 is opened in the next cycle S2, and the normal optical charge storage section of the normal optical signal charge Et (2) received and converted during the period S2. The transfer is completed in a period until the transfer to 40 is started (see FIG. 3C). The imaging of one frame of the normal image Zt in the next cycle S2 is performed by the normal optical signal charge Et (1).
Starting from the illumination of the normal pulse light Pt (2) in the cycle S2 performed before the reading of the data is completed, the same operation as described above is repeated.

On the other hand, the imaging of the fluorescent image Zk is performed as follows. During the period T1 in the latter half of the cycle S1, the signal charge of the light receiving unit 10 becomes empty, the normal optical transfer gate 20 and the excitation light transfer gate 30 are cut off, and the light receiving unit 10 can receive light. The fluorescent image Zk is received during the period of T1. That is, during the period T1 of the cycle S1, the pulse excitation light Pr (1) is irradiated (see FIG. 3D), and this pulse excitation light Pr
Fluorescence image Zk generated from living tissue 1 by irradiation of (1)
(1) is converted by the light receiving unit 10 into fluorescent signal charges Ek (1). When the fluorescent transfer gate 30 is opened, all the fluorescent signal charges Ek (1) converted by the light receiving unit 10 are simultaneously transferred and stored in the normal photocharge storage unit 40 (see FIG. 3E). . When the signal charge of the light receiving unit 10 becomes empty, the normal optical transfer gate 20 is shut off, and the light receiving unit 10 is ready to receive light.

The fluorescent signal charges Ek (1) stored in the fluorescent charge storage section 50 are sequentially transferred to the fluorescent horizontal shift register 70 for each scanning line of the image, and further converted as image signals by the fluorescent reading circuit 90. Read.
The process of reading the fluorescent signal charge Ek (1) from the fluorescent charge storage unit 50 is performed during the period T3, that is, the transfer of the fluorescent signal charge Ek (1) to the fluorescent charge storage unit 50 is completed and the fluorescent transfer gate 30 is shut off. After that, the fluorescence image Zk (2) generated by the irradiation of the pulse excitation light Pr (2) in the cycle S4 is converted into the fluorescence signal charge E by the light receiving unit 10.
After conversion to k (2), the fluorescent transfer gate 30
Is released, and is completed in a period until the transfer of the fluorescent signal charge Ek (2) to the fluorescent charge storage unit 50 is started.
(See FIG. 3 (f)). The imaging of the next one frame of the fluorescent image Zk starts with the irradiation of the fluorescent pulse light Pk (2) in the cycle S4 performed before the reading of the fluorescent signal charge Ek (1) is completed, and the same operation as described above is repeated. .

As described above, in order to read a small amount of signal charge obtained by receiving the weak fluorescent image Zk at a high S / N ratio, it is necessary to reduce the signal charge reading speed.
Reading the fluorescent signal charge Ek (1) for one image stored in the fluorescent charge storage unit 50 requires a time (period of 1/60 second or more) from the period S1 to the period S4. Therefore, the fluorescent image Zk is not read as a moving image, and an image with dropped frames is obtained.

Normal image Zt read at 1/60 second cycle
And fluorescent image Z read over 1/60 second or more
The image k is processed by the image signal processing circuit 8 so as to be displayed on the same screen, and is displayed by the display 9.

The control circuit 80 controls the illumination of the normal pulse light Pt, the irradiation of the excitation pulse light Pr, and the control of the timing for transferring the signal charges.

Next, a second embodiment of the present invention will be described. As shown in FIG. 4, the imager 100 according to the second embodiment has a light receiving unit 10 when capturing the normal image Zt.
Normal photocharge storage unit 40, normal optical horizontal shift register 60
In addition, when capturing an image in the form of a frame transfer type CCD image sensor constituted by a normal light reading circuit 80 and capturing a fluorescent image Zk, the light receiving unit 10, the fluorescent transfer gate 30, the fluorescent charge accumulating unit 50, the fluorescent horizontal shift register 70 In addition, an image is captured in the form of a frame transfer type CCD image sensor constituted by the fluorescent reading circuit 90.

In the second embodiment, unlike the first embodiment, the light receiving unit 10 and the fluorescent charge accumulating unit 50 are not directly connected via the transfer gate. The fluorescent signal charge Ek thus transferred is transferred to the fluorescent charge storage unit 50 by traversing the normal light charge storage unit 40, the normal light horizontal shift register 60, and the fluorescent transfer gate 30. Other configurations and operations are the same as those of the first embodiment.
Since k can be read out over a longer period of time than the imaging cycle of a normal image by being temporarily stored in the fluorescent charge storage unit 50, a high-quality fluorescent image with less noise can be obtained.

Next, a third embodiment of the present invention will be described. As shown in FIG. 5, the image pickup device 100 according to the third embodiment includes a light receiving unit 10, a normal light transfer gate 20, a normal light horizontal shift register 60, and a normal light reading circuit 80 when capturing a normal image Zt. The light receiving unit 1 is used for imaging in the form of a full frame transfer type CCD imaging device, and for imaging the fluorescent image Zk.
0, fluorescent transfer gate 30, fluorescent charge storage unit 5
0, fluorescent horizontal shift register 70 and fluorescent reading circuit 9
Frame transfer type CCD composed of 0
An image is captured in the form of an image sensor.

When capturing the normal image Zt, the light receiving section 1
Since there is no accumulation unit for accumulating the ordinary light signal charge Et received and converted by 0, the ordinary light signal charge Et is directly transmitted from the light receiving unit 10 via the ordinary light horizontal shift register 60 by the ordinary light reading circuit 80. Read as charge. That is, as shown in the timing chart of FIG. 6, the normal light signal charge Et (1) of the light receiving unit 10 is read as signal charge by the normal light reading circuit 80 before the irradiation of the excitation pulse light Pr (1) ( FIG. 6 (a), (c)
reference). Other configurations and operations are the same as those of the first embodiment. The fluorescent signal charge Ek (1) is temporarily stored in the fluorescent charge storage unit 50, and thus is over a time T3 longer than the normal image capturing cycle. (FIGS. 6 (d), (e), (f)
Since the reading is possible, a high-quality fluorescent image with less noise can be obtained.

Next, a fourth embodiment of the present invention will be described. As shown in FIG. 7, the image pickup device 100 according to the fourth embodiment is a full frame transfer type CCD configured by the light receiving unit 10, the normal light horizontal shift register 60, and the normal light reading circuit 80 when capturing the normal image Zt. When capturing an image in the form of an image sensor and capturing a fluorescent image Zk, the light receiving unit 10 and the fluorescent transfer gate 3
0, fluorescent charge storage unit 50, fluorescent horizontal shift register 70
In addition, an image is captured in the form of a frame transfer type CCD image sensor constituted by the fluorescent reading circuit 90.

In the fourth embodiment, unlike the third embodiment, the light receiving section 10 and the fluorescent charge storage section 50 are not directly connected via the transfer gate.
The fluorescent signal charge Ek received and converted by the light receiving unit 10
Is transferred to the fluorescent charge accumulating unit 50 by traversing the normal optical horizontal shift register 60 and the fluorescent transfer gate 30. Other configurations and operations are the same as those of the third embodiment. The fluorescent signal charges Ek can be read out over a longer time than the normal image capturing cycle by being temporarily stored in the fluorescent charge storage unit 50. Therefore, a high-quality fluorescent image with little noise can be obtained.

Next, a fifth embodiment of the present invention will be described. As shown in FIG. 8, when capturing the normal image Zt, the image pickup device 100 according to the fifth embodiment is arranged so as to oppose one side of each row of the photosensitive elements 11 arranged in a matrix and the photosensitive elements 11. A vertical transfer gate 16 for switching the blocking or opening of the transferred signal charge and receiving signal charges from the photosensitive elements 11 of each row, which are arranged opposite to one side of each row of the gates 16, in the column direction of the photosensitive elements 11. A light receiving unit 10 comprising a vertical shift register 17 for transferring,
When an image is taken in the form of an interline transfer type CCD image pickup device constituted by a normal light transfer gate 20, a normal light horizontal shift register 60 and a normal light reading circuit 80, and the fluorescent image Zk is taken, the photosensitive element 1 is used.
1. Light receiving unit 10 including vertical transfer gate 16 and vertical shift register 17, fluorescent transfer gate 30, fluorescent charge storage unit 50, fluorescent horizontal shift register 7.
In this case, an image is captured in the form of a frame interline transfer type CCD image pickup device constituted by 0 and a fluorescence reading circuit 90.

The fifth embodiment is different from the third embodiment in the internal structure of the light receiving section 10. When the normal image Zt is picked up, the light receiving section 10 receives and converts the light received by the photosensitive elements 11 arranged in a matrix. The optical signal charge Et is transferred to the vertical shift register 17 via the vertical transfer gate 16 and further transferred from the vertical shift register 17 to the normal optical horizontal shift register 60 via the normal optical transfer gate 20 for each scanning line of an image. It is sequentially transferred and read as an image signal by the normal light reading circuit 80.

When the fluorescent image Zk is picked up, the received and converted fluorescent signal charge Ek is supplied to the vertical transfer gate 1
6. Simultaneously transferred to the fluorescent charge storage unit 50 via the vertical shift register 17 and the fluorescent transfer gate 30, and further transferred from the fluorescent charge storage unit 50 to the fluorescent horizontal shift register 70 sequentially for each scanning line of the image to read the fluorescent light. The image is read by the circuit 90 as an image signal. Other configurations and operations are the same as those of the third embodiment. The fluorescent signal charges Ek can be read out over a longer time than the normal image capturing cycle by being temporarily stored in the fluorescent charge storage unit 50. Therefore, a high-quality fluorescent image with little noise can be obtained.

Next, a sixth embodiment of the present invention will be described. As shown in FIG. 9, when capturing the normal image Zt, the image pickup device 100 according to the sixth embodiment is arranged so as to face one side of each row of the photosensitive elements 11 arranged in a matrix and the photosensitive elements 11. The vertical transfer gate 16 for switching the blocking or opening of the transferred signal charge and the signal charge is received from the photosensitive element 11 of each row and arranged opposite to one side of each row of the vertical transfer gate 16, and the column direction of the photosensitive element 11 is received. An image is picked up in the form of an interline transfer type CCD image pickup device constituted by a light receiving section 10 composed of a vertical shift register 17 for transferring the image to a normal light horizontal shift register 60 and a normal light reading circuit 80. A light receiving unit 10 including a device 11, a vertical transfer gate 16, and a vertical shift register 17, a fluorescent transfer Over preparative 30, fluorescent charge accumulation portion 50 has a configuration for imaging in the form of a frame interline transfer type CCD imaging device configured by fluorescence horizontal shift register 70 and the fluorescence reading circuitry 90.

In the sixth embodiment, unlike the fifth embodiment, the light receiving section 10 and the fluorescent charge accumulating section 50 are not directly connected via the transfer gate.
The fluorescent signal charge Ek received and converted by the light receiving unit 10
Is transferred to the fluorescent charge accumulating unit 50 by traversing the normal optical horizontal shift register 60 and the fluorescent transfer gate 30. Other configurations and operations are the same as those of the fifth embodiment. The fluorescent signal charges Ek can be read out over a longer time than the normal image capturing cycle by being once stored in the fluorescent charge storage unit 50. Therefore, a high-quality fluorescent image with little noise can be obtained.

Next, a seventh embodiment of the present invention will be described. As shown in FIG. 10, when capturing the normal image Zt, the imaging device 100 according to the seventh embodiment is arranged so that the photosensitive elements 11 arranged in a matrix and one side of each row of the photosensitive elements 11 face each other. A normal optical vertical transfer gate 12 for switching the blocking or opening of the transferred signal charge, and a signal charge received from the photosensitive element 11 of each row, which is arranged opposite to one side of each row of the gate 12 and receives a row of the photosensitive element 11 An image is picked up in the form of an interline transfer type CCD image pickup device constituted by a light receiving section 10 comprising a normal light vertical shift register 14 which moves in the direction, a normal light horizontal shift register 60 and a normal light reading circuit 80, and a fluorescent image Zk is taken. In this case, the photosensitive elements 11 arranged in a matrix and the movement of signal charges arranged opposite to one side of each column of the photosensitive elements 11 are blocked or moved. A fluorescent vertical transfer gate 13 for switching emission and a fluorescent vertical shift register 15 arranged opposite to one side of each column of the gate 13 for receiving signal charges from the photosensitive elements 11 of each column and transferring the signal charges in the column direction of the photosensitive elements 11. In this case, an image is picked up in the form of an interline transfer type CCD image pickup device constituted by a light receiving section 10, a fluorescent horizontal shift register 70 and a fluorescent reading circuit 90.

The seventh embodiment differs from the fifth embodiment in the internal structure of the light receiving section 10, and the charge accumulating section for accumulating the fluorescent signal charges Ek is removed. When capturing the normal image Zt, the normal light signal charge E received and converted by the photosensitive elements 11 arranged in a matrix is used.
t is transferred to the normal light vertical shift register 14 via the normal light vertical transfer gate 12, and the normal signal charge Et is sequentially transferred from the shift register 14 to the normal light horizontal shift register 60 for each scanning line of an image. The normal signal charge Et for each scanning line transferred to the optical horizontal shift register 60 is read by the normal light reading circuit 80.

When capturing the fluorescent image Zk, the photosensitive element 1
The fluorescent signal charges Ek received and converted by the fluorescent light signal 1 are transferred to the fluorescent vertical shift register 15 via the fluorescent vertical transfer gate 13 and sequentially transferred from the shift register 15 to the fluorescent horizontal shift register 70 for each scanning line of the image. The charge Ek is transferred to the fluorescent horizontal shift register 70.
The fluorescence signal charge Ek for each scanning line transferred to the scanning line is read by the fluorescence reading circuit 90.

In the above configuration, there is no charge storage section for temporarily storing the fluorescent signal charge Ek, but the fluorescent signal charge Ek transferred to the fluorescent vertical shift register 15 receives the normal image Zt by the light receiving section 10 and the light receiving section 10 The normal optical signal charge Et converted by the normal optical vertical shift register 1
4 can be read from the fluorescent vertical shift register 15 without interfering with the reading operation. That is, the fluorescent vertical shift register 15 plays a role of a storage unit for temporarily storing fluorescent signal charges. Other configurations and operations are the same as those of the fifth embodiment. Since the fluorescent signal charge Ek is read out from the fluorescent vertical shift register 15 over a longer time than the normal image capturing cycle, the fluorescent signal charge Ek has less noise and high quality. An image can be obtained.

Next, an eighth embodiment of the present invention will be described. As shown in FIG. 11, the imaging device 100 according to the eighth embodiment is arranged so as to oppose one side of each row of the photosensitive elements 11 arranged in a matrix when capturing the normal image Zt. A normal optical vertical transfer gate 12 for switching off or opening the movement of the signal charge, and a signal charge is received from the photosensitive element 11 of each row and arranged opposite to one side of each row of the gate 12, and the column direction of the photosensitive element 11 is received. An image is picked up in the form of an interline transfer type CCD image pickup device constituted by a light receiving section 10 composed of a normal light vertical shift register 14, a normal light horizontal shift register 60 and a normal light reading circuit 80, and a fluorescent image Zk is taken. Sometimes the photosensitive elements 11 arranged in a matrix and the blocking or opening of the movement of signal charges arranged opposite to one side of each column of the photosensitive elements 11 are cut off. A fluorescent vertical transfer gate 13 to be replaced, and a fluorescent vertical shift register 15 disposed opposite to one side of each column of the gate 13 to receive signal charges from the photosensitive elements 11 in each column and transfer the signal charges in the column direction of the photosensitive elements 11. Unit 10, fluorescent horizontal shift register 70
In addition, an image is captured in the form of an interline transfer type CCD image sensor constituted by the fluorescent reading circuit 90.

In the eighth embodiment, unlike the seventh embodiment, the fluorescent vertical shift register 15 is not directly connected to the fluorescent horizontal shift register 70. Are transferred to the fluorescent horizontal shift register 70 by traversing the normal optical horizontal shift register 60. Other configurations and operations are described in Chapter 7.
Since the fluorescent signal charge Ek is read out from the fluorescent vertical shift register 15 over a longer time than the normal image capturing cycle, a high-quality fluorescent image with less noise can be obtained.

As described above, the imaging method and the imaging apparatus of the present invention can simultaneously capture a moving image of a normal image and a fluorescent image, and can be mounted in a small space.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram in which an imaging device of the present invention is applied to a fluorescent endoscope.

FIG. 2 is a schematic configuration diagram of a frame transfer / frame transfer type image pickup device;

FIG. 3 is a timing chart of an imaging operation of an imaging device including a storage unit for a normal image.

FIG. 4 is a schematic configuration diagram of another frame transfer / frame transfer type image pickup device;

FIG. 5 is a schematic configuration diagram of a full frame transfer / frame transfer type image pickup device.

FIG. 6 is a timing chart of an imaging operation of an imaging device that does not include a storage unit for a normal image.

FIG. 7 is a schematic configuration diagram of another full-frame transfer / frame transfer type image pickup device.

FIG. 8 is a schematic configuration diagram of an interline transfer / frame interline transfer type imager;

FIG. 9 is a schematic configuration diagram of another interline transfer / frame interline transfer type imager.

FIG. 10 is a schematic configuration diagram of an interline transfer / interline transfer type imager;

FIG. 11 is a schematic configuration diagram of another interline transfer / interline transfer type imager.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Light-receiving part 20 Normal light transfer gate 30 Fluorescence transfer gate 40 Normal light charge accumulation part 50 Fluorescence charge accumulation part 60 Normal light horizontal shift register 70 Fluorescence horizontal shift register 80 Normal light reading circuit 90 Fluorescence reading circuit 100 Image sensor

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 4C061 AA00 BB01 BB08 CC06 DD00 LL01 NN01 QQ02 QQ04 RR03 RR26 SS04 WW17 4M118 AA10 AB01 BA12 BA13 CA01 DA14 DB01 FA03 FA38 FA41 FA44 5C022 AA09 AB15 AB37 AC42 AC09 FA01 5C024 GA11 GA16 GA17 GA26 5C054 AA01 CA04 CC07 HA12

Claims (6)

[Claims] 1. A light receiving section comprising a large number of photosensitive elements arranged in a matrix for receiving light and converting the light into signal charges, receives normal light and fluorescent light at different timings, and receives the normal light And the received light amount of the fluorescence are converted into signal charges, respectively, and the first signal charge converted from the received light amount of the normal light is converted into a first output circuit for high-speed reading via a first horizontal shift register. And the second signal charge converted in the amount of received fluorescent light passes through a holding unit capable of holding the signal charge and passes through a second horizontal shift register to a second output circuit for low-speed reading An imaging method characterized in that the image is transferred to a camera. 2. A photodetector comprising a plurality of photosensitive elements arranged in a matrix for receiving normal light and fluorescent light at different timings and converting the amount of received normal light and the amount of received fluorescent light into signal charges. One light receiving unit, a first horizontal shift register for transferring the first signal charge converted from the amount of light received by the normal light to a first output circuit for high-speed reading, and the amount of light received by the fluorescent light is converted. A second signal charge holding unit for holding a second signal charge; and a second horizontal shift register for transferring the signal charge of the holding unit to a second output circuit for low-speed reading. Characteristic imaging device. 3. The method according to claim 2, wherein the second signal charge holding section is a second signal charge holding section.
The image pickup apparatus according to claim 2, wherein the image pickup device is a second signal charge storage unit that stores the signal charges. 4. The storage device according to claim 3, further comprising a first signal charge storage unit for storing the first signal charge, between the light receiving unit and the first horizontal shift register. An imaging device according to any one of the preceding claims. 5. One side of the photosensitive element in each row of the light receiving section,
One vertical signal for transferring the first signal charges converted by the photosensitive elements in each column to the first horizontal shift register and transferring the second signal charges to the second signal charge storage unit. 4. The device according to claim 3, further comprising a shift register.
An imaging device according to any one of the preceding claims. 6. A photosensitive element in each row of the light receiving section on both sides,
A first vertical shift register that transfers the first signal charges converted by the photosensitive elements in each column to the first horizontal shift register; and a second vertical shift register that transfers the second signal charges to the second horizontal shift register. 3. A second vertical shift register for transferring, the second vertical shift register also serving as the second signal charge holding unit.
An imaging device according to any one of the preceding claims.