WO2005115221A1

WO2005115221A1 - A reusable miniature camera head

Info

Publication number: WO2005115221A1
Application number: PCT/IL2005/000555
Authority: WO
Inventors: Elazar Sonnenschein; Minelu Sonnenschein; Amir Govrin; Shai Sheinberg
Original assignee: Medigus Ltd.
Priority date: 2004-05-31
Filing date: 2005-05-30
Publication date: 2005-12-08
Also published as: IL162251A0; US20070182842A1; IL179531A; IL179531A0; ATE429846T1; DE602005014231D1; KR20070046034A; AU2005247202A1; CA2568452A1; EP1765146B1; EP1765146A1

Abstract

The invention is a reusable miniature camera head (10) that can be attached to and detached from an object. The camera head comprises: a housing (18), a lens system (12), a solid-state sensor (14), components of an electronic driver (16), and an internal electrical connector (20) located at the proximal end of the housing and having a plurality of sockets (22) or pins (110) on its external face. The object has an external connector (24) for receiving the camera head. The internal and external electrical connectors comprise a plurality of pins or sockets arranged in matching patterns on opposing faces thereby allowing the camera head to be attached to or disconnected by engaging the two connectors. In preferred embodiments of the invention, the object to which the camera head is attached is an endoscopic or laparoscopic device, the solid-state sensor is a Charge Coupled Device (CCD), and the housing does not contain a printed circuit board.

Description

A REUSABLE MINIATURE CAMERA HEAD

Field of the Invention

The present invention relates to the field of remote imaging. Particularly

the invention relates to a reusable miniature camera head that can be

attached to and detached from an object.

Background of the Invention

Minimal access diagnostics and/or therapy, e.g. laparoscopy, interventional

flexible endoscopy, minimal access surgery, and percutaneous

interventional radiology, are generally carried out within the body cavities

or small incisions in the abdomen and therefore the person carrying out the

procedure cannot directly view the operating field. For this reason, the

ability to carry out such procedures is dependent on the imaging systems

that display the images obtained by the camera sensor focused on the scene.

The imaging systems comprise a miniature camera head based on solid-

state sensors, e.g. Charge Coupled Device (CCD) and permanently attached to the distal tip of the rigid, semi-rigid, or flexible endoscope and connected,

usually by means of a cable that runs through the length of the endoscope, to a power supply, computing device for processing the signals from the

CCD, and display means.

The high cost of rigid, semi-rigid, and flexible endoscopes dictates that they

must be reused for numerous procedures. This in turn dictates that they

must be sterilized between each procedure, which further increases the

expense, since they must be built using special techniques and special

materials to be able to withstand the harsh chemicals and/or high

temperatures and/or washing machines of the sterilization and cleaning

procedure.

The camera assembly is by far the most expensive part of an endoscope and

a significant reduction in the cost of the endoscopes and the procedures

carried out using them could be achieved, if a way could be found to

separate the camera head from the device after each use, discard the rest of

the device, sterilize or clean the camera head only, and then attach it to a

new rigid, semi-rigid, or flexible endoscope for the next procedure.

In co-pending International Patent Application WO2005/002210 by the

same applicant, the description of which, including reference cited therein,

is incorporated herein by reference in its entirety, there are described

methods for producing an imager assembly for a miniature camera head. As

the size of the CCD sensor on which the camera is based becomes smaller, a number of technical and practical problems have become apparent to the

inventors. These problems are centered round the fact that the motivation

behind using ever smaller sensors is to be able to produce smaller diameter

endoscopes, which will be able to enter smaller diameter lumens in order to

enable new therapeutic and diagnostic techniques. When the size of the

CCD sensor becomes smaller than that disclosed in the above mentioned

patent application, the size of the components of the electronic driver of the

camera becomes the limiting factor that has to be overcome. Additionally,

from a practical point-of-view, the detachable camera heads become so small

that it is difficult to handle them.

It is a purpose of the present invention to provide a miniature camera head

that is smaller than any camera head that is presently available.

It is another purpose of the present invention to provide a detachable

miniature camera head that can be attached to and detached from a rigid,

semi-rigid, or flexible endoscope.

It is an additional purpose of the present invention to provide solutions to

the problems that have arisen in trying to reduce the diameter of rigid,

semi-rigid, and flexible endoscopes. Further purposes and advantages of this invention will appear as the

description proceeds.

Summary of the Invention

The present invention is a reusable miniature camera head that can be

attached to and detached from an object. The camera head comprises: - a housing; a lens system at the distal end of the housing; a solid-state sensor located adjacent to the lens system; components of an electronic driver; and an internal electrical connector located at the proximal end of the housing and having a plurality of pins or sockets on its external face.

The camera head is attached to or disconnected from the object by engaging

or disengaging the internal electrical connector in or from an external

electrical connector that is fixedly attached to the object. The external

electrical connector comprises a plurality of sockets or pins arranged on its

face in a pattern matching that of the sockets or pins on the internal

connector

The camera head of the invention can be based on the use of any type of

semi-conductor detector, e.g. an Intensified Charge Coupled Device (ICCD);

an Electron Multiplying Charge Coupled Device (EMCCD); or a

Complementary Metal Oxide Semiconductor (CMOS) device, that is sensitive to radiation in any radiation band, e.g., X-ray, visible, or Near

Infra Red (NIR). In preferred embodiments of the camera head of the

invention the solid-state sensor is a Charge Coupled Device (CCD). In some

embodiments at least some of the components of the electronic driver are

located outside of the housing. In preferred embodiments, especially useful

in cameras comprising very small CCDs, the housing does not contain a

PCB and at least some of the components of the electronic driver are

attached directly to the back of the CCD.

In typical applications, the object to which the camera head of the

invention is attached is a rigid, semi-rigid, or flexible endoscope or

catheter.

Henceforth in this application whenever the word endoscope is used it is

to be understood in the broadest sense as including all types of rigid,

semi-rigid, and flexible endoscopes, including laparoscopes with and

without articulation sections, borescopes, catheters, etc.

In preferred embodiments of the invention, the camera head can be

sterilized either chemically or in an autoclave. In other preferred

embodiments of the invention, the camera head is a permanent part of a sterilizable distal tip, which can be detached and reattached to the

insertion tube of an endoscopic or laparoscopic device. The housing can have metallic electricity conducting strips arranged on

its outside surface and the external electrical connector has metallic

contacts arranged in such a way that they will engage the conducting

strips when the housing is pushed into contact with the electrical

connector. Preferably the housing hermetically isolates the lens system,

sensor, and components of the driver from the surrounding environment

and is fabricated from a material selected from the group comprising:

titanium, stainless steel, and polymers.

In some embodiments of the camera head of the invention, circuitry is

printed on the surface of one or more ceramic or polymer printed circuit

boards (PCBs) and some or all of the components of the electronic driver

are mounted on the PCBs. The electronic driver typically includes an

amplifying component comprised of an N-channel field effect transistor

(FET) or an amplifier circuit, wherein the amplifier circuit can be a

Maxim operational amplifier that includes several amplifying stages.

Some or all of the resistive components of the electronic driver can be

implemented by utilizing burn resistors.

The lens system of the invention typically comprises a plurality of lens that

together form an image with a field of view of between 60 and 160 degrees. In preferred embodiments of the invention, the lens system is designed for

carrying out a procedure selected from the following group:

(a) a gastroscopy procedure by forming an image with a field of view of 120 to 140 degrees;

(b) an ERCP procedure by forming an image with a field of view of 120 to 140 degrees in the motherscope and by forming an image with a field of view of 100 degrees in the baby scope;

(c) a colonoscopy procedure by forming an image with a field of view of 120 tol40 degrees;

(d) a gynecology procedure by forming an image with a field of view of 100 to 120 degrees;

(e) a bronchoscopy procedure by forming an image with a field of view of 80 to 100 degrees;

(f) an ENT procedure by forming an image with a field of view of 80 to 100 degrees; and

(g) a transgastric procedure by forming an image with a field of view of 100 tol40 degrees in the motherscope and by forming an image with a field of view of 100 to 120 degrees in the baby scope

In preferred embodiments of the camera head of the invention, the

diagonal size of the CCD chip is in the range from approximately

1.01mm to approximately 2.84mm and the diameter of the distal tip of the rigid, semi-rigid, or flexible endoscope is in the range from

approximately 1.6mm to approximately 3.5mm.

All the above and other characteristics and advantages of the invention will

be further understood through the following illustrative and non-limitative

description of preferred embodiments thereof, with reference to the

appended drawings in which like parts are designated by the same

reference number.

Brief Description of the Drawings

- Figs. 1 to 3 show a first embodiment of the reusable camera head of the invention;

- Figs. 4A to 4C show an embodiment of the camera head of the invention comprising external electric connectors;

- Figs. 5 to 7 show another embodiment of the reusable camera head of the invention;

- Fig. 8 shows the distal end of a disposable endoscope comprising a camera of the invention;

- Fig. 9 and Fig. 10 show the distal end of the endoscope of Fig. 8 with part of the sheath removed;

- Figs. 11 to Fig. 14 show another embodiment the camera head of the invention; - Fig. 15A, Fig. 15B, and Fig. 15C show respectively examples of configurations of the lens systems having 100 degree, 120 degree and 140 degree fields of view;

- Fig. 16 schematically shows a typical arrangement of a driver for the camera head of the invention that does not comprise a PCB;

- Fig. 17A and Fig. 17B show the electronic components assembly for a camera head comprising a 1/15" CCD chip;

— Fig. 19 shows the 1/15" CCD chip secured in a special jig; for removing the excess tape;

— Fig. 20 shows the CCD chip, legs, and wire terminals after most of the CCD tape has been cut away;

— Fig. 21 shows the CCD chip held in an especially designed holding jig;

— Fig. 22 shows how the wires from the electronic sub-assembly and the two capacitors are attached to the CCD wire terminals by soldering;

— Fig. 23 shows how an electrically insulating pad support is electrically connected to the driver assembly by soldering the pads to the CCD wire terminals;

- Fig. 24A and Fig. 24B show respectively the detachable distal tip of the invention attached to and detached from the distal end of an insertion tube of an endoscope;

- Fig. 25A and Fig. 25B are perspective views showing the detachable distal tip of the invention; - Fig. 26 is a perspective view showing the distal end of an insertion tube of an endoscope adapted to mate with the detachable distal tip of the invention; and

- Fig. 27 is a cross-sectional view taken along the longitudinal axis of Fig. 24A.

Detailed Description of Preferred Embodiments

Figs. 1 to 3 show a first embodiment of the reusable camera head 10 of the

invention. Referring first to Fig. 1, camera head 10 is a closed housing 18,

preferably cylindrically shaped, with a lens system 12 at its front end. The

camera head 10 is shown in Fig. 1 attached to external electrical connector

24. External electrical connector 24 has around its outer perimeter clasps

28, which can be for example leaf springs, which are used to hold external

electric connector in position in a socket at the distal end of the endoscope.

Signal transmission and electric power supply wires 30 are attached to the

back face of external electrical connector 24 and are in electrical contact

with a plurality of pins 26 (see Fig. 2) arranged in a pattern on the front

face of connector 24.

Fig. 2 and Fig.3 show the camera head 10 with part of the housing 18 removed to reveal the interior of the camera head. The camera head 10 is

shown disconnected from the external electrical connector 24 in these

figures. Generally, in all of the figures herein, the internal electrical connections between components of the camera head are not shown for clarity.

Inside of the housing 18 is a front wall 32 that supports the lens system 12

on its front face and the CCD 14 on its rear face. The lens system 12 is of

conventional design for endoscopic or laparoscopic instruments. The lenses

are made of material that can withstand repeated sterilization, particularly

autoclaving, procedures. Suitable examples are, for example N-SK10 and N-

SF8 optical glasses supplied by Schott Glass Technologies or glasses with

Tg>530 centigrade. The lens system typically comprises a plurality of lens

that together (depending on the combination of lenses used) form an image

with a field of view of between 60 and 160 degrees and depth of focus

suitable from 1mm to 100mm in front of the camera head and project the

acquired image on the face of the CCD. Examples of configurations of the lens systems having 100 degree, 120 degree and 140 degree fields of view

are shown in Fig. 15A, Fig. 15B, and Fig. 15C respectively. The field of view

of the lens system of the camera is selected according to the type of

procedure to be carried out by the endoscope to which the camera will be

attached. Some procedures are performed using two endoscopic devices: a

"mother scope" which is used to gain access to the region of the procedure

within the body and a second, smaller diameter, "baby scope" that is used to carry out the procedure. The field of view of the baby scope is typically

smaller than that of the mother scope. Examples of various procedures in the visible radiation band and the corresponding field of view are shown in

Table 1.

Table 1

Similar tables can be constructed for procedures carried out while observing

in bands other than the visible, for example, for angiography where the

CCD would be sensitive in the x-ray band.

Examples of commercially available CCD chips 14 for use in camera head

10 are ICX256/7FKW CCD (1/10" diagonal) manufactured by Sony, and

LC99267FSB CCD (1/9") by Sanyo. Sony has also developed a 1/15" CCD sensor (ICX421FKZ). Sensors having CCD chips with even smaller diagonal

dimensions are presently being designed. In preferred embodiments of the invention, the lens system 12 is attached to the face of the CCD 14 using a

heat resistant optically transparent adhesive that has a thermal expansion

coefficient that will prevent damage to the camera head during sterilization

procedures carried out in an autoclave.

Also shown inside the housing of camera head 10 are electronic components

of electronic driver 16. For the larger sized CCD chips, as is done in prior

art camera heads, some or all of the components of driver 16 can be

mounted on one or more ceramic or polymer, for example Teflon, printed

circuit boards (PCBs) 34 (shown in Fig. 5, but not seen in Fig. 2 or Fig.3).

Circuitry is printed on the surface of the PCB and the electronic

components, which include an amplifying component, are attached. An N-

channel field effect transistor (FET) is usually used as an amplifying

component in driver designs. In a preferred embodiment of the invention,

an amplifier circuit such as a Maxim operational amplifier that includes

several amplifying stages implements the amplifying element. In order to

reduce the physical dimensions of driver 16, the resistive components may

be implemented by utilizing burn resistors. The burn-resistors are created

in the PCB conducting lines, and serve as electrical links between the

electrical components. In this way the space consumed by the resistive

components becomes negligible. In the preferred embodiment of the detachable camera head, especially for

those comprising the smallest sized CCD chips, no PCB is used in the

camera head. The components of the driver are attached directly to the back

surface of the CCD chip, to the connector, or to the inside walls of the

housing. A typical arrangement of driver 16 for the camera head of the

invention that does not use a PCB is schematically shown in Fig. 16. On the

back of the CCD chip 14 (1/10" - ICX257FKW) are glued transistor 160

(2S2029 ROHM), resistor 162 (510hm), capacitor 164 (InF, 50V), and

capacitor 166 (lOOnF, 16V). The internal connections are shown in Fig. 16.

The fourteen tabs on the CCD chip and the top electrode of the resistor are

connected to the internal electrical connector 20 (see Fig. 2). It is stressed

that the arrangement shown in Fig. 16, and especially the component

numbers and parameters given in parenthesis, are given merely to

illustrate one way of implementing driver 16 and is not meant to limit the

invention in any way. An example of another method of assembly of a

miniature camera comprising a 1/10" CCD chip will be described

hereinbelow.

Referring again to Fig. 2 and Fig. 3, all signal transmission lines and

electrical supply wires to and from the driver 16 and CCD 14 are connected

to contacts on the inside face of internal electric connector 20. The contacts

on the inner face of internal electric connector 20 are in electrical contact

with a plurality of sockets 22 arranged in a pattern on the outside face of connector 20. The pins 26 on the front face of external electric connector 24

fit into the sockets 22 on the outside face of internal electric connector 20,

thus establishing electrical continuity between the components inside

housing 18 of reusable camera head 10 and signal transmission and electric

power supply wires 30 in the endoscope, the distal ends of which are

electrically connected to the pins in external electric connector 24. In

addition, since the external electrical connector is fixedly attached to the

endoscope by means of clasps 28, the pins 26 and sockets 22 act as a "quick

connector" for attaching the camera head 10 to the endoscope.

For the electrical connectors shown in Fig. 2 and Fig. 3, the pins and sockets

are arranged internally on the faces of the respective connectors. In Figs. 4A

to 4C is shown another arrangement for making the electrical contact

between the interior of the camera head and its exterior. As seen in Fig. 4A,

the housing 18' of camera head 10" has a rectilinear shape. Housing 18' is

made of an electrically insulating material and in the planar upper and

lower surfaces are longitudinal slots containing metal electricity conducting

strips 22' that are electrically connected to the inside. The external

electrical conductor is in two parts 24' that are fixedly attached to the walls

of a socket in the distal end of the endoscope and spaced apart such that

camera head 10" can be inserted between them. On the face of each part 24'

of the external electric conductor are metallic contacts 26' that are arranged in a matching pattern to the conducting strips 22' on the top and bottom surfaces of housing 18' and to the signal transmission and electric power

supply wires 30. Metallic contacts 26' are preferably leaf springs that will

provide electrical contact and also will act as a "quick connector" holding the

camera head at the distal tip when it has been pushed into place and

allowing it to be detached easily simply by pulling it away from the

endoscope.

Figs. 4B and 4C show Camera head 10' held in place between the two parts

24' of the external electric connector. The arrangement shown in Figs. 4A to

4C can be utilized to reduce the lateral dimensions of the camera head

under certain conditions.

The housing 18 completely surrounds the components of camera head 10,

thereby hermetically isolating the components of the camera head, except

for the front surface of the first lens in the optical system and the outer face

of the electrical connector 22, from contact with the surrounding

environment. Thus, as long as all the components of the camera head are

heat resistant up to the temperatures reached in an autoclave, no special

precautions have to be taken when using the camera or during the

sterilization procedure. The housing must be resistant to sterilization

solutions such as CIDEX and EtO and autoclave sterilization at 134°C and

pressure of 2.3 bar. Suitable materials from which the housing can be fabricated are, for example, titanium, stainless steel, or a polymer, such as

Teflon or one of its derivatives.

Figs. 5 to 7 show another embodiment of the reusable camera head 10' of

the invention. In this embodiment, electronic driver 16 is not inside of

housing 18 of the reusable camera head 10', but is located proximally of the

external electrical connector 24. This makes the driver 16, part of the

disposable endoscope and therefore the components can be made having less

strict tolerances and are therefore less expensive than those of the

embodiment described hereinabove. This follows not only because the driver

does not have to be able to survive the elevated temperature of autoclave

sterilization, but also because the requirements of circuit stability, etc. are

much less stringent for a unit that is only required to work once than for a

unit which is designed to operate repeatedly over many thousands of cycles.

Skilled persons will also realize that the driver 16 can be produced as an

ASIC component, greatly reducing the cost of the camera head.

Additionally, the cable that is used to connect between the external

connector and the video processor in the present invention can be designed

to a much lower standard than is possible with prior art cameras.

Figures 11 to 14 show another way of implementing the camera head of the

invention. In this embodiment of the camera head 100, the internal

connector is replaced with a separate insulating conductor support 102. The camera head is shown without the lens system mounted on the CCD 14 and

with the housing that surrounds and protects it removed. The components

of driver 16 are attached to the CCD 14 or the conductor support 102

without the use of a PCB as described with reference to Fig. 16. In Figs. 11

and 12 the CCD 14 has ten tabs connected to CCD conductors 104, which

extend to and are bent into slot 106 in the top of conductor support 102.

Projecting out of the proximal face of the conductor support 102 are two

guide pins 108 for aligning the conductor support 112 with a matching

connector 124 (Fig. 13) and for guiding the ten pins on the conductor

support 112 into matching bores on the face of the connector 124. Fig. 11

shows an embodiment in which the ten pins 110 are rigid and slide into a

metal sheath lining the inside of the bores on the face of connector 124. In

this embodiment the end of each pin is pushed against the bent end of the

corresponding CCD conductor 104 in slot 106 and soldered to it. Fig. 12

shows an embodiment in which spring probes 112 are installed in the

conductor support 102. In this case, it is not necessary to solder the CCD

conductors to the probes, since the force exerted by the compressed springs

in the probe 102 when it is inserted into the bore in connector 124 will be

sufficient to provide electrical continuity. In Fig. 13 is shown a connector

124 for use with the embodiment shown in Fig. 12. A ten-conductor camera

cable 130 is attached to the proximal face of connector 124. On the distal face of connector 124 can be seen ten bores 126 comprising metallic cores

against which the ends of the spring probes 112 are compressed as the guiding pins 108 are pushed into the two guiding bores 126. In order to

ensure good electrical connection between the contacts on the internal and

external connectors, a conducting layer, for example, GB MATRIX TYPE by

Shin-Etsu Chemical Co., Ltd. Can be attached between connectors 102 and

124 (shown in Fig. 14), e.g. by attaching it to the distal face of connector 124

(Fig. 13). Fig. 14 is a side view showing the conductor support 102 with its

attached CCD assembly connected to camera cable 130 by means of cable

connector 124. Fig. 8 shows the distal end of a disposable endoscope 36

comprising a camera head 10,10' of the invention. The choice of a

disposable endoscope is merely for illustrative purposes and the camera

head of the invention can also be used with any type of endoscope. The

endoscope need not be disposable after a single use, but the entire device or

some of its components can be sterilized separately from the camera head

and reused for subsequent procedures.

Shown on the distal face of endoscope 36 is the surface of the first lens of

lens system 12; a gasket 38, which surrounds the lens system to prevent

liquids from entering the interior of endoscope; two light fibers 44, which

illuminate the area viewed by the camera; an irrigation nozzle 42, to clean

the lenses; and two working channels 40, through which the

surgeon gastroenterologist can insert the tools necessary to carry out the

procedure. The endoscope shown in Fig. 8 is illustrative only and the reusable camera head of the invention can be attached to rigid, semi-rigid, or flexible endoscopes comprising many different configurations and accessories. As specific examples, the endoscope can comprise only a single working channel or the illumination can be provided by a single fiber, which ends in a light ring around the perimeter of the distal face.

Fig. 9 and Fig. 10 show the distal end of the endoscope 36, with part of the sheath removed. From these two figures, it can be seen how the camera head 10,10' is slid into (and out of) socket 46 in the distal end of endoscope 36 and is pushed into (and out of) the external electrical connector 24 that is attached to the endoscope.

Referring to Figs. 8 to 10, the working channels 40 have a diameter of 0.8- 1.2mm, the light fibers 44 a diameter of 0.3-0.6mm, and the diameter of the camera head is 3mm. The external diameter of the endoscope is less than 5mm and if the endoscope has only one working channel it will have an external diameter of up to 4mm. In table 2 are shown dimensions for endoscopes that will use detachable camera heads without a PCB and the CCD's presently available or under development.

Table 2

The presently preferred embodiment of the assembly procedure for the

miniature camera head of the invention will now be described. The

procedure described herein pertains to the 1/10" CCD chip but is provided

merely to illustrate the invention and is not intended to limit the scope of

the invention in any manner. For example, it is expected that the same

procedure will be used mutatis mutandis with a 1/15" and smaller CCD

chips. The CCD chip has the shape of a square having sides of

approximately 1.8mm length. Therefore only a transistor and a resistor are

attached directly to the CCD chip and the two capacitors, which comprise

the remainder of the electronic driver are added to the assembly at a later

stage.

Because of the small size of the components and also to insure the accuracy

of the assembly, the components are handled either manually using micro

tweezers or a vacuum pick-and-place device or automatically with an

automatic pick-and-place machine and the assembly is carried out using a

stereomicroscope such as Nikon SMZ 800.

The first stage of the procedure is the assembly of the electronic

components. The transistor (e.g. type 2sa2029, pack 0402) is placed on a flat

surface using, for example, micro tweezers. Next UV glue, such as Loctite type 3494 is applied on one side of the transistor. To insure accurate application of the glue, a glue dispenser, for example an ESD 1400 glue

dispenser, is used. After the glue is cured using a UV light curing system

such as Dymax blue wave 50, a resistor (e.g. 39 ohm, pack 0201) is placed on

the transistor. Fig. 17A shows the electronic components assembly. In the

figure it can be seen how the five- sided termination 174 at one end of

resistor 172 is pushed into contact with one of the three conducting legs 176

of transistor 170. After another layer of UV glue is applied and cured, the

electronic components are connected to each other and to jumper wires 178

using precision soldering devices, e.g. manual soldering stations like Weller

MT 1500 or a high-power diode laser such as one of those produced by Dilas

GmbH systems.

Now, using the soldering device, the two capacitors are soldered to each

other and to jumper wires as shown in Fig. 17B. Capacitor 180 has a

capacitance of lOOnF and capacitor 182 has a capacitance of InF.

The next stage of the procedure is to prepare the CCD so that the

electronic components can be attached to it. Fig. 18 shows the 1/10" CCD

chip (Sony ICX257) with a plastic holder surrounding the tape, as it is

supplied by the manufacturer. The plastic holder surrounding the tape is

removed from the CCD component and the CCD tape is secured in a

specially designed jig (shown in Fig. 19). Initially the CCD tape is secured with the photosensitive side of the chip facing upwards and a glass spacer, to which the lens system will eventually be attached, is

glued to the CCD's glass side using optical glue such as 140-M light

curing glue by DYMAX Corporation.

The CCD is now released from the jig, turned over such that the glass is at

the bottom, and it is replaced in the special jig. Most of the CCD tape is now

cut away using a scalpel. Fig. 20 shows the results of this operation

comprising the CCD chip 184 with its legs 186 and CCD wire terminals 188.

A small strip of the CCD tape 190 is left to maintain the mechanical

integrity of the chip.

The chip is now transferred to the especially designed holding jig shown in

Fig. 21. The chip is centered on chip support 192 and held firmly in place by

tongue 194. Z stage 196 is now raised past the chip support 196 causing

CCD legs 186 to bend upwards around the sides of tongue 194 until they are

bent into the configuration shown in Fig. 22. Referring again to Fig. 21, side

walls 198 are advanced out of the interior of the holding jig to support the

CCD wire terminals 188. The Z stage is now moved upwards until it

releases the CCD legs. The tongue 194 is now retracted into the jig and

repositioned 0.3mm from the edge of the CCD chip in order to clamp the

chip in place while leaving room to attach the electronic components. The

holding jig is now moved to the micromanipulator table where the electronic

assembly will be completed. The previously prepared electronic components assembly (Fig. 17A) is

placed on the CCD and secured to it by using UV glue such as 204-CTH by

DYMAX Corporation using a precise glue dispenser such EFD ULTRA 1400

+ micros dispense pen system and UV light curing system. The wires from

the electronic sub-assembly and the two capacitors (Fig. 17B) are attached

to the CCD wire terminals by soldering as shown in Fig. 22. The next step

in the assembly procedure is shown in Fig. 23. An electrically insulating pad

support 200 comprising nine electrically conducting pads 202 and a hole 204

is placed between the CCD wire terminals above the capacitors and

electrically connected to the driver assembly by soldering the pads to the

CCD wire terminals. Finally, one wire is passed through hole 204 and

soldered to the resistor and nine more wires are soldered to each of the pads

202. Once the electrical connections have been completed the entire

assembly, from the back of the CCD to the top of the pads, is encapsulated

using UV glue.

The encapsulated CCD is now turned over and a lens holder comprising a

typically cylindrically shaped sleeve and the remainder of the elements of

the lens system is glued to the CCD on the side where the glass is located.

The encapsulated CCD is now placed into a suitably shaped titanium or

stainless steel housing with the lens holder preferably projecting out of the front end of the housing. The ten wires at the top of the assembly are threaded through the titanium housing and the titanium housing is sealed

to the lens-housing holder using biocompatible epoxy, for example EPO-

TEK 353 ND.

Next, the 10 wires are connected by soldering or crimping to ten male micro

connectors in a conductor support. The connectors comprise special pins

such as Mill-Max Mfg. Corp cat. no. 8210 or Interconnect Devices, Inc.

IDINET penta 0.

Finally the housing is filled with epoxy and closed by placing the connector

support in its proximal end. Any excess glue is then wiped off to complete

the creation of a totally closed (encapsulated) structure.

The housing of a camera head assembled according to the above described

procedure and based on a 1/10' CCD will be on the order of 3-4mm in

diameter. From a practical point-of-view handling such a small camera

head, for example when removing it from an endoscope, sterilizing it, or

reattaching it to the same or another endoscope for another procedure will

be an awkward procedure for the practitioner to carry out. To overcome this

problem, in a preferred embodiment of the invention, the miniature camera head will be a permanent part of a sterilizable distal tip, which can be

detached and reattached to the insertion tube of an endoscopic or

laparoscopic device. Fig. 24A and Fig. 24B show respectively the detachable distal tip of the

invention 300 attached to and detached from the distal end of an

insertion tube of an endoscope. In these and the following figures, the

sheath surrounding the insertion tube and the articulation section, if the

endoscope comprises one, is not shown.

Figs. 25A and 25B are perspective views showing the distal and

proximal faces respectively of the detachable distal tip of the invention.

Distal tip of the invention 300 is made of a monolithic block of

biocompatible material, e.g. a plastic polymer, stainless steel and

Titanium. A number of bores through which the various channels of the

endoscope pass to the distal tip pass longitudinally through the distal

tip. In the figures can be seen bores for the working channel 340,

irrigation channel 342, and two light channels 344. A miniature camera

head 310 of the type described hereinabove is embedded into distal tip

300 with the front lens of camera flush with the distal end of the distal

tip and the internal connector 20 of the camera flush with the proximal

end. In the outer surface of proximal end of distal tip 300 are several

grooves 306, each having a slot 304 at its distal end that are used for

fastening distal tip 300 to insertion tube 302 as will be described hereinbelow. Fig. 26 is a perspective view showing the distal end of an insertion tube

of an endoscope 308 adapted to mate with the detachable distal tip of the

invention. The interface between the distal end of the insertion tube 302

and the detachable distal tip 300 must be designed such that continuity

of the various channels in the insertion tube will be preserved until the

distal face. This is accomplished by extending the tubes that define these

channels through the insertion tube such that they project out from the

distal face. As can be seen in the figures, the irrigation channel 42,

working channel 40, and two channels for the optical fibers 312 will slide

into matching bores 342, 340, and 344 respectively in the distal tip. As a

result when pressed together the extended channels slip tightly into the

bores forming a tight seal between the insertion tube as well as

providing mechanical strength to the connection between the two parts.

To prevent possible damage to the optical fibers when the distal tip is

attached or detached, channels 312 can be metal tubes with electro

polished interiors or metal tubes filed with Grin lenses to diffuse the

light and, if necessary, lenses at the distal end to properly distribute the

light in the field of view of the camera. The optical fiber light guides in the insertion tube can end at the interface and light exiting the fibers

coupled into the proximal ends of channels 312, thereby providing optical

continuity from the light source located proximally of the endoscope to

the distal face. It is also possible to use light emitting diodes (LEDs) oor polymer light emitting diodes (PLEDs) located at the distal end of the insertion tube instead of illumination fibers. The internal electrical

connector 20 of the camera 30 located on the proximal end of the distal

tip 300 is forced into electrical contact with the external electrical

connection 124 on the distal end of the insertion tube 302, thereby

permitting transfer of electrical power and signals to/from the camera

head from/to the peripheral equipment at the proximal end of the

endoscope as has been described hereinabove. Because of the very small

size of the contacts on the camera head and distal end of the insertion

tube, there is a possibility that good electrical connection might not be

established; therefore it is preferred to use a matrix type conducting

layer at the interface between the contacts as described hereinabove.

Fig. 27 is a cross-sectional view taken along the longitudinal axis of Fig.

24A. In this figure it can be clearly seen how clasps 308, on the distal end of

the insertion tube 302, fit into grooves 306 on distal tip 300 and snap into

slots 304 to hold the distal tip in place.

Although embodiments of the invention have been described by way of

illustration, it will be understood that the invention may be carried out with

many variations, modifications, and adaptations, without departing from its

spirit or exceeding the scope of the claims. In particular it is to be

understood that, although the camera head of the invention has been

described herein for use in endoscopy and laparoscopy, it is equally well- suited for use with any other type of probe or device in any conceivable

application requiring the use of a miniature camera.

Claims

1. A reusable miniature camera head that can be attached to and detached from an object, said camera head comprising: a housing; a lens system at the distal end of said housing;

— a solid-state sensor located adjacent to said lens system; components of an electronic driver; and an internal electrical connector located at the proximal end of said housing; wherein, said camera head is attached to or disconnected from said object by engaging/disengaging said internal electrical connector in/from an external electrical connector fixedly attached to said object.

2. A camera head according to claim 1, wherein the solid-state sensor is selected from the following group:

— a Charge Coupled Device (CCD);

— an Intensified Charge Coupled Device (ICCD);

— an Electron Multiplying Charge Coupled Device (EMCCD); and

— a Complementary Metal Oxide Semiconductor (CMOS) device.

3. A camera head according to claim 1, wherein at least some of the components of the electronic driver are located outside of the housing.

4. A camera head according to claim 2, wherein the housing does not contain a PCB and at least some of the components of the electronic driver are attached directly to the back of the CCD.

5. A camera head according to claim 1, wherein the object is a rigid, semirigid, or flexible endoscope.

6. A camera head according to claim 1, wherein said camera head can be sterilized.

7. A camera head according to claim 6, wherein the sterilization is carried out in an autoclave.

8. A camera head according to claim 6, wherein the sterilization is carried out using chemicals.

9. A camera head according to claim 1, wherein said camera head is a permanent part of a sterilizable distal tip, which can be attached and detached to the distal end of the insertion tube of an endoscopic or laparoscopic device.

10. A camera head according to claim 1, wherein the housing has metallic electricity conducting strips arranged on its outside surface and the external electrical connector has metallic contacts arranged in such a way that they will engage said conducting strips when said housing is pushed into contact with said electrical connector.

11. A camera head according to claim 1, wherein the housing hermetically isolates the lens system, sensor, and components of the driver from the surrounding environment.

12. A camera head according to claim 1, wherein the housing is fabricated from a material selected from the group comprising: titanium; stainless steel; and - polymers.

13. A camera head according to claim 1, wherein circuitry is printed on the surface of one or more ceramic or polymer printed circuit boards (PCBs) and some or all of the components of the electronic driver are mounted on said PCBs.

14. A camera head according to claim 1, wherein the electronic driver includes an amplifying component selected from: an N-channel field effect transistor (FET); or an amplifier circuit.

15. A camera head according to claim 14, wherein the amplifier circuit is a Maxim operational amplifier that includes several amplifying stages.

16. A camera head according to claim 1, wherein some or all of the resistive components of the electronic driver are implemented by utilizing burn resistors.

17. A camera head according to claim 1, wherein the lens system comprises a plurality of lens that together form an image with a field of view of between 60 and 140 degrees.

18. A camera head according to claim 17, wherein the lens system is designed for carrying out a procedure selected from the following group:

(b) an ERCP procedure by forming an image with a field of view of the camera head of the invention 120 to 140 degrees in the motherscope and by forming an image with a field of view of 100 degrees in the baby scope;

(c) a colonoscopy procedure by forming an image with a field of view of 120 to 140 degrees; (d) a g necology procedure by forming an image with a field of view of 100 to 120 degrees;

(g) a transgastric procedure by forming an image with a field of view of 120 to 140 degrees in the motherscope and by forming an image with a field of view of 100 to 120 degrees in the baby scope.

19. A camera head according to claim 1, wherein the diagonal size of the CCD chip is in the range from approximately 1.01mm to approximately 2.54mm.

20. A camera head according to claim 19, wherein the diameter of the distal tip of the endoscope is in the range from approximately 1.6mm to approximately 3.5mm.

21. A camera head according to claim 17, wherein the first lens is glued to the CCD.