TITLE

Portable imaging device

FIELD OF THE INVENTION

The present invention relates generally to an imaging system, and more particularly to a portable endoscopic imaging device of the imaging system.

BACKGROUND OF INVENTION

Minimally invasive procedures or surgeries (MIP or MIS), including -endoscopic, laparoscopic, endoscopically-assisted, or laparoscopically-assisted procedures, are known and offer benefits to a patient for example, limited incisional trauma, decreased pain, limited scars, decreased hospitalization, and earlier return to a normal functional state. To perform such procedures endoscopic imaging devices are employed. A typical endoscopic imaging system includes a monitor, a light source, a power source, a video processing unit, of the imaging system and an endoscope. Conventionally, the various units are permanently or semipermanently installed within a cabinet, which occupies a substantial portion of the operating room. In addition, the shifting and relocation of the cabinet becomes a difficult task because of the size and weight.

Several techniques and devices have been employed to make the imaging system compact and portable. One of such devices in particular adaptable to

evaluation of swallowing dysfunction comprises a housing having various units such as the light source, endoscopic camera, video recording device, video monitor, and power supply each unit being stored in several compartments of the housing. Once the various units are stored in the housing, the housing can be hand transferred to a patient's location. However, the storing and setting up of the devices may be time consuming and involve special skills. Another device attempts a reduction in size of the housing by splitting the electronic circuit boards and accommodating them along with the illumination control means in the same housing. In addition, the thickness of the casing walls is reduced to achieve lightweight and damper members are provided to ensure protection of the electronic assembly from external forces. However, additional shielding is needed for noise reduction, which makes the maintenance more time consuming and difficult because of increased number of components.

In light of the above discussion, Applicant's have recognized the desirability of a compact and portable imaging device for endoscopic application that overcomes one or more of the limitations of the prior art devices, while maintaining one or more of their advantages. Further, alternative cost effective solutions to achieve the desired outcome are sought. Hence, the imaging device should be simple in design and be portable, lightweight, economic, and easy to use.

OBJECTS OF THE INVENTION

It is therefore an object of the invention to propose a compact and portable

imaging device in an imaging system in particular for endosopic application , which eliminates the disadvantages of the prior art.

Another object of the invention is to propose a compact and portable imaging device in an imaging system in particular for endosopic application, which eliminates the requirement for additional shielding to achieve noise reduction.

A still another object of the invention is to propose a compact and portable imaging device in an imaging system in particular for endosopic application, which is light weighted, simple, and easy to operate.

A further object of the invention is to propose a compact and portable imaging device in an imaging system in particular for endosopic application, which is portable, compact and cost-effective.

SUMMARY OF INVENTION

Accordingly there is provided a compact and portable imaging device in an imaging system, in particular for endoscopic application, the system having an endoscope insertable into the body of a patient for capturing video image from the examination site, the device comprising a base unit accommodating an illumination assembly a camera module converting reflected light in the endoscope to video signals; and an electronic circuitry, the electronic circuitry comprising a first electronic subassembly housed in the base unit for modulation

and isolation of the video signals; a second electronic subassembly housed in a remote unit, for receiving electrical signal from the camera module for processing and transmitting the processed electrical signals.

BRIEF DESCRIPTION OF ACCOMPANYING DRAWINGS

FIG. 1 illustrates an endoscopic imaging system having a portable and compact imaging device, in accordance with the present invention;

FIG. 2 illustrates a functional block diagram of the base unit of the portable and compact imaging device, in accordance with the present invention;

Fig 3 is an exploded view of the base unit illustrating the packaging of the various components with respect to the housing, in accordance with an embodiment of the present invention;

FIG. 4 illustrates a stacked configuration of the first electronic subassembly and the power supply module, in accordance with an embodiment of the present invention;

FIG. 5a illustrates an assembly of the light source subassembly, the illumination control means and the heat sink, in accordance with an embodiment of the present invention;

FIG. 5b is an exploded view of an assembly of the illumination control system and the heat sink, in accordance with an embodiment of the present invention; and

FIG. 6 illustrates a remote unit, in accordance with an embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Although the present invention will be described in conjunction with several embodiments as depicted in the figures, a person skilled in the art will easily recognize that numerous additional embodiments will be well within the scope of the present invention, wherein the scope is defined by the claims provided. Hence, the detailed description that follows is intended merely to illustrate the present invention, and not intended to limit the scope of the claimed invention in any way. Definitions of the technical terminologies the used in the claims are intended to ensure that the readers will not consider to limit the scope of these terminologies to the specified preferred embodiments only, as described in this detailed description. These definitions are given by way of example only, without limitation.

The terms "electronic component", "electronic sub-assembly", "electronic assembly" and "electrical component" are intended to refer to any component or device that operates using electricity. Moreover, the term 'component' is meant

to encompass any device that is a single component device or a device that combines a number of components together. In other words, it is intended that the terms be defined as broadly as would be understood by those skilled in the art. The use of the term "electronic" or "electrical" is not intended to be limiting in any manner, unless so specified herein. Before delving into the specifics of the present invention, a general overview is provided below.

The terms "fiber optics" and "fiber optic cable" as used herein are intended to typically refer to flexible optical conductors comprising a multiplicity of light conductive fibers, e.g. glass fibers, in the form of a bundle or strand; generally, the bundle includes an adhesive, matrix or the like for interconnection of the fibers, and a sheath, sleeve or the like is arranged around the fiber bundle; the bundle ends are arranged in planes, generally by grinding vertically to the axes of the fibers; when used for illumination of a cavity, one of the planes is arranged near a light source and referred to as "entrance plane" while the other plane is placed near the site that is to be illuminated and is referred to as the "exit plane."

The term "light source" as used herein refers to a light source producing light or a light beam. The light source can be a cold light source, wherein, the light or the light beam contains only a negligible amount of heat radiation, that is, only very little radiation in the infrared range of the spectrum, if any. The light sources may also be chosen from other kinds of light sources. Various light sources are known to those skilled in the art, such as a halogen light source,

xenon light source, metal halide bulb, LED, tungsten filament bulb, arc light source and the like. Further, the light source may sometimes include an integrated reflector for providing a focused beam of light.

Once the scope of some of the critical terms has been defined, to get a more complete understanding of the present invention, a detailed description of the various embodiments of the present invention in conjunction with the illustrations, is provided below.

Referring to FIG. 1, a portable and compact imaging device 110 adaptable to an imaging system 100 is illustrated, in accordance with the present invention. The portable imaging device 110 includes a base unit 112, a remote unit 114, a connector 116, and a fiber optic cable 118. The fiber optic cable 118 is connected to an endoscope 120. The endoscope 120 is coupled to the remote unit 114 by an optical coupler 150. The base unit 112 is coupled to a display 130 by a video cable 160a, the display 130 showing the endoscopic video images. A recording means 140 is connectable to the base unit 112 by a video cable 160b. The connector 116 connects the base unit 112 and the remote unit 114. In an embodiment of the present invention, the connector 116 is a cable connector. The cable connector 116 transmits video signals from the remote unit 114 to the base unit 112 and transmits power from the base unit 112 to the remote unit 114. In another embodiment of the invention, the connector 116 is a wireless communication link between the remote unit 114 and the base unit 112. Further, the remote unit 114 may be battery powered. Further, the endoscopic imaging

system 100 includes a camera module. In an embodiment of the present invention, as illustrates in FIG.l, the camera module is incorporated along with the remote unit 114 in the camera handle. Henceforth, unless mentioned otherwise, the remote unit 114 includes the camera module.

The endoscopic imaging system 100 can be used for assisting minimally invasive procedures, wherein the endoscope 120 is inserted into the body of the patient and the video image captured from the site of examination is displayed on the display 130. The portable imaging device 110 acts as a video image capturing unit, a source for the light and a video processing unit. Although the present invention describes the use of imaging device 110 in conjunction with surgical applications, various other possible use of the imaging devices are known to those skilled in the art. For example, such portable imaging devices have broad reaching application in the field of computer inspection, customs inspection, plumbing, mining, automobile mechanics, veterinary medicine, aviation, remote control devices, safety equipment, monitoring devices, police investigations and in a variety of other settings in which detailed inspection is desired. Further, the medical use of the imaging device 110 includes therapeutic and diagnostic medicine, inspection of body canals and openings, surgical applications such as MIS, MAP, NOTES and the like, dental applications, phototherapy, and others.

The portable imaging device 110, as illustrated in FIG.l, typically includes a base unit 112, a remote unit 114, a connector 116, and a fiber optic cable 118. Referring now to FIG. 2, a functional block diagram of the base unit 112 of the

portable imaging device 110 is provided, in accordance with an embodiment of the present invention. The base unit 112 further includes a light source subassembly 210, a cooling module 220, a power supply 230, a first electronic subassembly 240, a housing 250, an illumination control means 260, an indicator module 270, a fiber optic receptacle 280, and a heat sink 290. The light source subassembly 210 provides light for illuminating the site of examination. The light source subassembly 210 includes a light source 212, a reflector 214, and a light source holder 216. The light source 212 and the reflector 214 are attached to the light source holder 216. The heat sink 290 is coupled to the light source subassembly 210. The heat sink 290 is provided to dissipate the heat generated by the light source assembly 210. The heat sink assembly 290 is also attached to the fiber optic receptacle 280. The fiber optic receptacle 280 acts as an optic port and provides a slot to align the receptor end of the fiber optic cable 118 (as shown in FIG. 1) with the beam of light generated by the light source subassembly 210. The cooling module 220 is placed adjacent to the heat sink 290 such that cooling module 220 blows cool air on the heat sink 290, the light source subassembly 210 and an illumination control means 260. The cooling module 220 draws the cooling air such that air is sucked from the areas surrounding the power supply module 230 and the first electronic subassembly 240. Thus, the cooling module 220 controls the rise in temperature of the base unit 112 by dissipating the heat generated by the light source subassembly 210, the power supply module 230 and the first electronic subassembly 240. The power supply module 230 powers the cooling module 220, the light source subassembly 210, the first electronic subassembly 240, and the remote unit 114

(shown in Fig. 1). In an embodiment of the present invention, the power supply module 230 has two major supply modules, a low voltage module 232 and a high voltage module 234. The low voltage 232 module is mainly made up of transformer and the high voltage module 234 is mainly made up of ballast. The high voltage module 234 provides power supply to the Light source subassembly 210 and the cooling module 220. The low voltage module 232 provides power supply to the first electronic subassembly 240 and the remote unit 114, wherein the remote unit 114 includes the camera module. The first electronic subassembly 240 modulates, controls and isolates the video signals received from the remote unit 114, the video signal received via the connector 116. In an embodiment of the present invention, the first electronic subassembly 240 includes a timer circuit 242 and a video isolation circuit 244. The timer circuit 242 is attached to the indicator module 270. The first electronic subassembly 240 also includes output ports 246 where the display 130 and the recording device 140 can be connected. The display 130 is used to view the video images from the workspace. The housing 250 encloses the various components of the base unit 112 and provides provisions for effective functioning of the cooling module 220 as discussed in one of the co-pending application, the co-pending application has been provided as a reference. The illumination control means 260 controls the illumination intensity of light that is supplied at the entrance plane of the fiber optic cable 118. The detail of the illumination control system 260 has been discussed in details in another co-pending application provided as reference.

In the light of the above description in FIG. 1 and FIG.2, the endoscopic imaging

system 100 comprises of two essential flows. The first being the flow of light for illuminating from the light source subassembly 210 to the workspace to be visualized. The second being the flow of the video signals from the workspace to the display 130. The following paragraphs explain these flows and the associated system modules.

The light originating from the light source 212 is transformed into a focused beam of light by the reflector 214. The focused beam of light passes through the illumination control means 260, which is located between the light source 212 and the fiber optic receptacle 280. The illumination control means 260 controls the intensity of light beam that passes through the fiber optic receptacle 280. The light beam is thereafter, transmitted through the fiber optic cable 118 to the endoscope 120. The light beam passes through the endoscope 120, and illuminates the workspace to be visualized.

Once the site is illuminated, the object reflects the light and the reflected light passes through the objective lens of the endoscope 120 and further transmitted to the remote unit 114. The camera module in the remote unit 114 converts the reflected light to video signal by an in-built image-processing unit. Thereafter, the video signal is passed to the first electronic subassembly 240 through the connector 116. The connector 116 is attached to the video isolation circuit 244 by a connection port 248. The video signals are modulated and isolated by the video isolation circuit 244. The video isolation circuit 244 also includes video output ports 246. The output ports 246 provide the video signal to the display

130 and recording device 140 through the video connectors 160a and 160b. The display 130 and recording device 140 are used to view and/or record the video images from the workspace.

The following paragraphs describes in details the various sub assemblies, components, and modules of the portable imaging device 110. The detailed description would include the constitution level details and the functional details of the modules/sub-assemblies. In addition, the detailed description ascertains that the portability and compactness are achieved by the novel arrangement and placement of the various components, modules and sub-assemblies.

Fig 3 is an exploded view of the base unit 112 illustrating the packaging of the various components with respect to the housing 250, in accordance with an embodiment of the present invention. The housing 250 is a four-piece assembly and comprises a front panel 310, a top cover 320, a bottom plate 330, and a middle panel 340. The front panel 310 is fitted on the bottom plate 330 with a supporting plate 318. The supporting plate 318 is also attached to the middle panel 340 at an attachment member 342. A fastening member attaches the supporting plate 318 to the bottom plate 330 and the middle panel 340. The top cover 320 is fitted on the middle panel 340 and tightened by the knurl screws 322. The knurl screws 322 can be released by hand. Hence, the removal of the top cover 320 during maintenance or light source 212 replacement is tooless. The housing 250 can be made of metal, alloy, carbon fiber, heat resistant plastic, glass, composites, ceramic, and the like. The housing 250 provides protection to

the inside components. The housing 250 also helps in dissipating the heat produced by the components inside the housing 250 and in reducing the EMI / EMC effect on first electronic subassembly 240 and power supply module 230 from electromagnetic interference caused by other electronic & electrical equipments in the surrounding environment of the light source 212 during the functioning of the imaging device 110.

The front panel 310 provides an attachment arrangement for various components such as the indicator module 270 and the indicator PCB 314, the front panel on/off switch 316 and the connection port 248. The front panel 310 provides an opening 312 for fitting the fiber optic receptacle 280. The front panel 310 also provides a window 313 for accommodating a knob of the illumination control means 260. An EMI filter 344 is mounted on rear of the middle panel 340. The EMI filter 344 is electrically connected to the Mains On/off Switch. This EMI filter 344 is used to suppress common mode noises and differential mode noises. Generally, these filters eliminate electromagnetic interferences created by the equipment and the component itself. A safety micro-switch 346 is also installed in a frame mounted on the middle panel 340. This switch 346 is used to shut off the power supply to the light source when the top cover 320 is removed.

The bottom plate 330 is used for fitting various modules of the base unit 112 such as the light source subassembly 210, the cooling module 220, the illumination control means 260, and the heat sink 290. The first electronic subassembly 240 and the power supply module 230 comprising the high voltage

module 234 and the low voltage module 232 are arranged in a stacked configuration on same side of the cooling module 220. The stacked configuration has been explained in detail in conjunction with FIG. 4.

FIG. 4 illustrates the stacked configuration of the first electronic subassembly 240 and the power supply module 230, in accordance with an embodiment of the present invention. The stacked configuration conserves space in the housing 250. As stated above, in an embodiment of the present invention, the power supply 230 has two major supply modules, a low voltage module 232 and a high voltage module 234. The high voltage module 234 comprises mainly of a ballast therefore it is heavy and generates a high amount of heat. Therefore, the high voltage module 234 is placed in the bottom of the stacked configuration. The high voltage module 234 is covered with a ballast casing 402. Functionally the ballast casing 402 provides an EMI/EMC shield, a protective covering and dissipates the heat produced by the high voltage module 234. The low voltage module 232 and the first electronic subassembly 240 is placed above the high voltage module 234 such that they are fitted on top of the ballast casing 402. A PCB chassis 404 covers the first electronic subassembly 240 and it is fitted on the top of the ballast casing 402. Functionally the PCB chassis 404 provides an EMI/EMC shield, a protective covering and dissipates the heat produced by the first electronic subassembly 240. The ballast casing 402 and the PCB chassis 404 has numerous openings 406. The openings 406 are created to facilitate the flow of air over the first electronic subassembly 240 and the power supply module 230. Also the openings 406 reduce the overall weight of the light source subassy

210. The embodiment of the present invention illustrates the openings 406 in the circular and rectangular configuration, however, numerous shapes other and their variations may occur to those skilled in the art, such as, triangular, polygonal, square and the like.

FIG. 5a in conjunction with FIG. 5b describes the assembly of the light source subassembly 210, the illumination control means 260 and the heat sink 290. FIG. 5a illustrates the assembly of the light source subassembly 210, the illumination control means 260 and the heat sink 290, in accordance with an embodiment of the present invention. FIG. 5b is an exploded view of the assembly of the illumination control means 260 and the heat sink 290, in accordance with an embodiment of the present invention.

The heat sink 290 includes a front flange 502, a rear flange 504, and a base plate 506. The base plate 506 connects the front flange 502 and the rear flange 504 such that they are placed at a fixed distance from each other and are parallel to each other. The heat sink 290 is fixed on a C plate 508 by fastening members 510. The C plate 508 is fixed to the bottom plate 330, thereby stabilizing the complete heat sink 290. The fastening members 510 are each placed in atleast one first slot 512 having a multi-step configuration wherein the profile of the slot decreases towards the C plate 508. This arrangement provides a leeway for fixing the heat sink 290 according to the desired optical alignment for different types of light source subassemblies 210. The heat sink 290 can be made of aluminum, copper, alloys, steel and the like.

The rear flange 504 has an extension member 514 for sliding, holding, aligning and for removably fitting the light source subassembly 210 on the heat sink 290. Extension member 514 is configured in such a manner that it is congruent with the light source holder 216. A hand operated knurl screw 516 is provided to removably fit the light source subassembly 210 on the rear flange 504. A second slot 518 is provided in the rear flange 504. The second slot 518 extending through the extension member 514. The second slot 518 provides a tolerance to accommodate thermal expansion of the light source holder 216 as well as the rear flange 504 and the extension member 514. Further, the second slot 518 accommodates the wiring that supply electric power to the light source 212.

The front flange 502 has fins 520 to increase the surface area for dissipating the heat generated by the light source subassembly 210. The front flange 502 also has a cutout section 522 to fit the illumination control means 260. The front flange 502 provides a stub 524 for accommodating the fiber optic receptacle 280. The fiber optic receptacle 280 is snuggly fitted on the stub with a ring member 526 in between. The ring member 526 fits inside the fiber optic receptacle 280 and has metal balls inserted in the body. The arrangement creates a snap fit arrangement for the fiber optic cable 118 when inserted in the fiber optic receptacle 280. Further, the ring member 526 and ball arrangement ensures proper alignment of the entrance plane of fiber optic cable 118 and the beam of light coming from light source 212. In addition, the illumination control means 260 is attached to the cut-out section 522 on the front flange 502. Lastly, a thermal protection plate 528 covers the heat sink 290 along with the light

source subassembly 210. The thermal protection plate 528 is fitted on the heat sink 290 by means of a hand operated knurl screws 530. The thermal protection plate creates a barrier between the light source 212 and the top cover 320, blocking the direct transmission of heat to the top cover 320. The thermal protection plate also helps in dissipating the heat generated by the light source 212.

In the embodiments of the present invention described above, the heat sink 290 is a single unit. However, in various other embodiments of the present invention, the heat sink be made up of one or more components. For example, in an embodiment of the present invention, the front flange 502 and the rear flange 504 can be arranged such that they have a flexibility of changing the distance as well as the angle between them. This can be achieved by an arrangement for sliding the front flange 502 and the rear flange 504 on the base plate 506 with a fixing arrangement at a desired distance and angle. Changing the distance and the angle between the front flange 502 and rear flange 504 provides a flexibility to accommodate different types of light source subassembly.

Referring now to FIG. 6, the remote unit 114 is illustrated, in accordance with an embodiment of the present invention. The remote unit 114 includes a top cover 610, a bottom cover 620, a front cover 630, a camera module 640, a white balance circuit 650, a ball socket means 660, a switch interface 670, and assembly features 680. As shown in the FIG. 6, the remote unit is the camera handle, which is coupled to the endoscope 120 by a optical coupler 150. The top

cover 610, the bottom cover 620, and the front cover 630 forms an enclosed space for housing the camera module 640 and the white balance circuit 650. The top cover 610 includes a slot 612 and some of the assembly features 680. The slot 612 is used to .affix the switch interface 670 to the top cover 610. As shown in Figure 6, the slot 612 also includes circular holes so that the switch interface 670 is in contact with the white balance circuit 650. The assembly features 6 in the top cover 610 also provide support for the white balance circuit 650 to be placed in an inclined fashion with respect to the top cover 610. Similarly, the bottom cover 620 also provides a first assembly features 614 for coupling the top cover 610 to the bottom cover 620. In addition, the first assembly features 614 in the bottom plate 620 provide support to the white balance circuit 650. Further, a second assembly features 614 are provided in the bottom cover 620 to accommodate the ball socket means 660. The ball and socket means 660 is provided to support the end of the connector 116 coupled to the white board circuit 650 and the camera module 640. In an embodiment of the present invention, the ball and socket arrangement 660 includes a silicon ball 662 housed in a polypropylene socket 664. The ball and socket arrangement provides flexibility to the connector 116 and increases the maneuverability of the remote unit 114 integrated with the camera handle. Hence reducing the damage to the connector 116. In addition, the ball and socket means 660 is particularly useful for medical applications wherein the instrument has to cleaned and sterilized, as the ball and socket arrangement 660 ensures proper sealing of the camera handle at the entry point of the connector 116.

Moving on to the white balance circuit 650 that is positioned between the top cover 610 and the bottom cover 620. The white balance circuit 650 provides the user with capability to compensate for the differences in color temperature of the light from the light source 212 and the surrounding light and further lock a desired color setting. The white balance circuit 650 includes a micro-switch 652 and LEDs 654. The white balance circuit 650 is coupled to the camera module 640 where the parameters corresponding to the desired color setting are stored. When the micro-switch 652 is pressed the color compensation is activated, consequently when the desired color setting are achieved the micro-switch 652 is pressed again, and the desired color settings are locked. In an embodiment of the present invention, one of the LEDs 654 turns green indicating a white balance lock. The other LED 654 is to indicate the power supply to the remote unit 114. The LED 654 are coupled to the slot 612 in the top cover 610.

As illustrated above, the white balance circuit 650 is incorporated in the remote unit 114. However, various other embodiments may be obvious to those skilled in the art. For example, in an embodiment of the present invention, the white balance circuit 650 may be incorporated in the base unit 112. In another embodiment of the present invention, there may be two white balance circuits 650 one provided in the base unit 112 and another provided in the remote unit 114.

The front cover 630 is provided to protect and house the camera module 640. Also, the front cover 630 includes provision for coupling the front cover 630 with

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the optical coupler 150. Further, appropriate sealing is provided between the window 632 in the front cover 630 and the camera module 640. The camera module 640 includes a camera chip 642 and an image processing circuit 644. In an embodiment of the present invention, the camera chip 642 is a 1/3-inch CCD chip which senses the light coming from the endoscope 120, and converts the light to an electric signal that is sent to the image processing circuit 644. In various other embodiment of the present invention, the camera chip 642 can be a CMOS chip, a Vi inch CCD chip, a ¹ A inch CCD chip, a 2/3 inch CCD chip, 3CCD sensor, and the like. Further, the camera chip may be sensitive to different kind of light spectrum, such as infrared, ultraviolet, visible light, fluorescence spectrum, or a combination thereof. The image processing circuit 644 receives the electric signal from the camera chip and processes the signal. The processed signal is then passed to the base unit 112 via the connector 116. In an embodiment of the present invention, the processing of the signal includes amplification of the signal, filtering out of noise from the signal, analog to digital conversion, frequency filtering, image corrections, phase modulation, signal amplitude and frequency modulation, and the like. In addition, in an embodiment of the present invention, the image processing circuit 644 can be a programmable chip, wherein the various parameters relating to signal processing and camera chip can be adjusted.

As illustrated in the various embodiments above, the remote unit 114 is incorporated as the camera handle. However, various other embodiments of the remote unit 114 may be obvious to those skilled in the art. For example, in an

embodiment of the present invention, the remote unit 114 may be a compact module comprising the image processing circuit 644 and the white balance circuit 650. The image processing circuit 644 and the white balance circuit 650 are together termed as second electronic subassembly. The remote unit 114 is connected to the camera chip 642 and the base unit 112 via connectors to carry electrical power and data signals. In addition, remote unit 114 may be integrated with the connector. In another embodiment of the present invention, the remote unit 114 may be realeasably connected with the camera chip 642 and the base unit 114 via the connectors.

In the light of the above description, the portability and compactness of the portable imaging device 110 is achieved by a novel configuration and arrangement of the various components and modules. The paragraphs below draw attention to some of the aspects of the present invention that contribute to the compactness and portability.

The light source subassembly and the heat sink housed in the base unit realizes a modular, compact, and multifunctional arrangement. Further, the illumination control unit is integrated with the heat sink. The light source and the reflector are integrated such that a focused beam of light is provided at the optic port, hence, eliminating the need for a lens system to focus the light. The heat sink also functions as a mounting unit for the light source. Additionally the heat sink accommodates the alignment of the light source, the illumination control system and the optic port. The heat sink also serves as the mounting for the illumination

control unit. Hence, the heat sink integrates and aligns the various components of the light source subassembly. Therefore, enabling the light source subassembly to be housed in the base unit along with the various other modules and sub-assemblies. In addition, since the light source is integrated with a reflector most of the heat generated is localized in front of the light source, hence, fins are provided only at the front section of the heat sink, further allowing reduction in the size and weight. Further, to reduce the weight of the complete assembly the heat sink, illumination control system, mounting bracket, are made of lightweight material such as aluminum and aluminum alloys.

The present invention provides a stacked configuration of the first electronic subassembly and the power module in the base unit. In an embodiment of the present invention, the electronic subassembly includes video isolation circuit board, and timer circuit. The power supply module includes the ballast, and the transformer. The stacked up arrangement of the various component allows for ample space for other modules to be fitted in. In addition, the mounting chassis and casing for the PCB and ballast also enable efficient cooling of the electronic circuitry. Further, in an embodiment of the present invention, the ballast is at the bottom of the stack. Hence, preventing a direct contact with the high voltage components during maintenance and bulb replacement, thus realizing safety.

The portability and compactness of the portable imaging device is also realized by accommodating the electronic circuits partially or completely in the remote unit. Accommodating the electronic circuitry in the remote unit and the base unit

eliminates the need for an additional module for video signal and image processing. In addition, the electronic circuitry accommodated in the remote unit does not require noise-protection circuits, as the remote unit is located far from the heavy electronic devices.

Apart from the portability and compactness, the embodiments of the present invention provide various other advantages such as ease of handling, safety, and easy maintenance. The ease of maintenance of the base unit is achieved by providing hand-releasable fastening means. The said fastening means are provided for coupling the top cover of the base unit to the middle panel, for coupling the thermal protection plate with the heat sink, for holding the bulb holder in the rear flange of the heat sink, for coupling the fiber optic receptacle to the stub of the heat sink's front flange. In addition, various safety features are provided in the base unit, for example, a video isolation circuit is provided to protect the electronic circuitry from back surge coming from the TV, monitor, recording device. A safety micro-switch is provided to shut down the bulb as soon as the top cover is lifted. As explained above, the ballast containing high voltage elements is placed at the bottom of the stack for safety. Hence, the portable imaging device achieves various other advantages as well apart from portability and compactness.

While the present invention has been illustrated by description of several embodiments, it is not the intention of the applicant to restrict or limit the scope of the appended claims to such detail. Numerous other variations, changes, and

substitutions will occur to those skilled in the art without departing from the scope of the invention.