This invention relates to scanned beam systems and, more particularly, to scanned beam endoscopes.
Video endoscopes have been in general use since the 1980s for viewing the inside of the human body. Endoscopes are typically flexible or rigid devices that have an endoscope tip including an imaging unit, such as a digital camera or a scanned beam imager, configured for collecting light and converting the light to an electronic signal. The electronic signal is sent up a flexible tube to a console for display and viewing by a medical professional such as a doctor or nurse.
Scanned beam endoscopes are a fairly recent innovation, and an example of a scanned beam endoscope is disclosed in U.S. patent application Ser. No. 10/873,540 (“'540 application”) entitled SCANNING ENDOSCOPE, hereby incorporated by reference and commonly assigned herewith.
The endoscope tip 120 and distal tip 118 thereof are configured for insertion into a body cavity for imaging internal surfaces thereof. In operation, responsive to user input via the handpiece 1112, the scanning module of the distal tip 118 scans a beam of light over a FOV, collects the reflected light from the interior of the body cavity, and sends a signal representative of an image of the internal surfaces to the console 110 for viewing and use by the medical professional.
In operation, the distal tip 118 is inserted into a body cavity. The illumination optical fiber 138 outputs a beam 144 that is shaped by the beam shaping optical element 140 to form a shaped beam 146 having a selected beam shape. The shaped beam 146 is transmitted through an aperture in the center of the MEMS scanner 136, reflected off a first reflecting surface 148 of the interior of the dome to the front of the scanner 136, and then reflected off of the scanner 136 as a scanned beam 150 through the dome 133. The scanned beam 150 is scanned across a FOV and reflected off of the interior of a body cavity. At least a portion of the reflected light from the FOV (e.g., specular reflected light and diffuse reflected light also referred to as scattered light) is collected by the detection optical fibers 132. Accordingly, the reflected light collected by the detection optical fibers 132 may be converted to an electrical signal using optical-electrical converters, such as photodiodes, and the signal representative of an image may be sent to the console 110 for viewing on the monitor 104.
While the scanned beam endoscope 100 is an effective endoscope, the distal tip 118 has a diameter that is typically larger than desired. It may be desirable to reduce the overall bulkiness and size of the distal tip 118 so that the size of an incision made for insertion of the distal tip 118 can be reduced. Reducing the size of the distal tip 118 may also be desirable to reduce patient discomfort when the endoscope is inserted into a preexisting opening in the body. Also, in some applications, it may be desirable to selectively position the illumination optical fiber 138 and/or the detection optical fibers 132 within the scanning module 128 to improve the performance characteristics of some aspects of the distal tip 118.
Scanned beam endoscopes, endoscope tips, scanned beam imagers, and methods of use are disclosed. In one aspect, a scanned beam endoscope includes a light source and an endoscope tip. The endoscope tip includes an illumination optical fiber having an output end and an input end coupled to the light source. The endoscope tip further includes a scanner positioned to receive a beam output from the output end of the illumination optical fiber and operable to scan the beam across a FOV. The scanner includes a plurality of openings extending therethrough, and the openings may be defined by the structure of the scanner such as the openings between a scan plate and gimbal and the gimbal and frame of the scanner. One or more light detection elements may be positioned to receive light reflected from the FOV through at least one of the openings in the scanner.
In another aspect, a method of collecting light reflected from a FOV is disclosed. The method includes scanning a beam across a FOV using a scanner. The method further includes transmitting at least a portion of light reflected from the FOV through at least one opening in the scanner for collection with at least one light detection element.
In another aspect, a scanned beam endoscope includes a light source and an endoscope tip. The endoscope tip includes an illumination optical fiber having an output end and an input end coupled to the light source. The endoscope tip further includes a scanner positioned to receive a beam output from the output end of the illumination optical fiber and operable to scan the beam across a FOV. The output end of the illumination optical fiber may be laterally positioned in relation to the scanner. One or more light detection elements may be positioned to receive light reflected from the FOV.
In another aspect, a method of scanning light across a FOV is disclosed. The method includes transmitting a beam from a location lateral in relation to a scanner and redirecting the beam to the scanner. The method further includes scanning the redirected beam across the FOV.
In another aspect, a scanned beam endoscope, includes a light source operable to provide light and an endoscope tip. The endoscope tip includes an optical fiber having an output end and an input end coupled to the light source and a scanner positioned to receive a beam output from the output end of the optical fiber and operable to scan the beam across a FOV. A central normal axis of the scanner is oriented at a non-zero angle relative to a longitudinal axis of the endoscope tip. A converter is provided that is operable to covert optical signals characteristic of light reflected from the FOV to electrical signals. The scanned beam endoscope further includes a display coupled to receive the electrical signals from the converter, the display being operable to show an image characteristic of the FOV.
In yet another aspect, a method of scanning a beam across a field of view (FOV) from an endoscope tip includes scanning the beam across the FOV using a scanner. A central axis of the FOV is oriented at a non-zero angle relative to a longitudinal axis of the endoscope tip.
The teachings disclosed herein are also applicable to scanned beam imagers and bar code scanners.
Apparatuses and methods for scanned beam endoscopes, endoscope tips, and scanned beam imagers are disclosed. Many specific details of certain embodiments are set forth in the following description and in
Turning now to
In various embodiment, the scanner 185 may be a 2D MEMS scanner, such as a bulk micro-machined MEMS scanner, a surface micro-machined device, another type of conventional MEMS scanner assembly, or a subsequently developed MEMS scanner assembly. The scanner 185 may be configured to scan one or more beams of light at high speed and in a pattern that covers an entire FOV or a selected portion of a 2D FOV within a frame period. As known in the art, such MEMS scanners may be driven magnetically, electrostatically, capacitively, or combinations thereof. For example, the horizontal scan motion may be driven electrostatically and the vertical scan motion may be driven magnetically. Electrostatic driving may include electrostatic plates, comb drives or the like. Alternatively, both the horizontal and vertical scan may be driven magnetically or capacitively.
The scanner 185 may include a plurality of openings formed therein. Openings 182a and 182b are defined by the gimbal ring 172, and the scan plate 174 and its associated torsion arms 188. Openings 184a and 184b are formed in the scanner 185 and are defined by the frame 163, and the gimbal ring 172 and its associated torsion arms 188. As best shown in
The dome 164 may include a partially reflective interior reflective surface 176 for redirecting light emitted from the illumination optical fiber 170 to the scanner 185 and allowing light scanned from the scanner 185 to pass therethrough. In some embodiments, the dome 164 may be configured to provide optical power for shaping light it reflects to the scanner 185 and light scanned from the scanner 185 that passes through the dome 164. One embodiment of a suitable dome 164 is disclosed in the aforementioned '540 application. Such a dome is configured to selectively reflect and transmit light having a particular polarization direction. In other embodiments, the dome 164 may not have any optical power and a fixed intermediate reflective structure may be disposed between the surface 176 and the scanner 185.
In operation, light may be input into the input end 169 of the illumination optical fiber 170 using a light source (not shown) and emitted from the output end 171 of the illumination optical fiber 170 as beam 194. The beam 194 may be received by the beam shaping optical element 180, which is configured to focus the beam 194 to a selected shaped beam 196 that has a beam diameter smaller than the diameter of the aperture 178 through which it passes. After shaping and passing through the aperture 178 in the scan plate 174, the shaped beam 196 is reflected from an interior reflective surface 176 of the dome 164 to the reflective surface 175 of the scanner 185. As previously discussed above, the dome 164 may be configured to partially or fully collimate the shaped beam 196. Then, the scanner 185 and its associated reflective surface 175 scans the shaped beam 196 as a scanned beam 200 across the FOV. As the scanned beam 200 passes through the dome 164, it may be further shaped to a selected beam shape such as a beam having a selected beam waist distance from a distal end 177 of the dome 164. The scanned beam 200 is reflected off of the interior of a body cavity in which the distal tip 160 is positioned in. The reflected light (e.g., specular reflected light and diffuse reflected light also referred to as scattered light) from the FOV passes through the dome 164 and is received by respective collection ends 173 of the detection optical fibers 168 that are selectively positioned to receive the reflected light through one or more openings 182a-182b and 184a-184b in the scanner 185. Optical signals representative of characteristics of the FOV may be further processed to define an image.
The distal tip 200 has many of the same components that are included in the distal tip 160 of
As with the distal tip 160, in the embodiment of the distal tip 200 shown in
In operation, the optical fiber 281 outputs a beam 294 from the output end 285 and a portion of the beam 294 is redirected by the beam splitter 292 as redirected beam 295 to a collimation optical element 296. The collimation optical element 296, which may be one or more lenses, collimates or partially collimates the redirected beam 295 shown as beam 298. The scanner 286, which may be any of the aforementioned scanner configurations, scans the beam 298 as a scanned beam that is transmitted through the housing 280 or a window therein across a FOV 288. A central axis 306 of the FOV 288 is oriented at a non-zero angle relative to the longitudinal axis 302. Light reflected from the FOV is transmitted through the housing 280 and collected by the collection mirror 284. The light collected by the collection mirror 284 is reflected to the beam splitter 292, which transmits a portion of the light reflected from the collection mirror 284 to the optical element 290. The optical element 290 may be a curved mirror that focuses the light received from the beam splitter 292 and directs the light received from the beam splitter 292 back therethrough to the output end 285 of the optical fiber 281 for collection and transmission to an optical-electrical converter. Thus, in such an embodiment, additional detection optical fibers are not necessary because the optical fiber 281 acts as both an illumination optical fiber and a detection optical fiber.
In operation, according to one embodiment, the distal tip 240 is placed within a body cavity. Responsive to user input via the handpiece 236, the distal tip 240 scans light over the FOV. Reflected light from the interior of the body cavity is collected by the distal tip 240. A photonic or electrical signal representative of an image of the internal surfaces is sent from the distal tip 240 to the console 229 for viewing on the monitor 222 and diagnosis by the medical professional. According to some embodiments, detection optical fibers, such as those shown in the embodiment of
The video processor and controller 254 also controls the operation of the other components within the control module 224. The control module 224 further includes a real time processor 262, which may, for example, be embodied as a PCI board mounted on the video processor and controller 254. The real time processor 262 is coupled to a light source module 256, a scanner control module 260, a detector module 264, and the video processor and controller 254. The scanner control module 260 is operable to control the scanner of the distal tip 240 and the detector module 264 is configured for detecting light reflected from the FOV.
The light source module 256, which may be housed separately, includes one or more light sources that provides the light energy used for beam scanning by the distal tip 240. Suitable light sources for producing polarized and/or non-polarized light include light emitting diodes, laser diodes, and diode-pumped solid state (DPSS) lasers. Such light sources may also be operable to emit light over a range of wavelengths.
Responsive to user inputs via the handpiece 236, a control signal is sent to the video processor and controller 254 via the control line 268. The video processor and controller 254 transmits instructions to the real time processor 262. Responsive to instructions from the real time processor 262, light energy is output from the light source module 256 to the endoscope tip 240 via an optical fiber 258. The optical fiber 258, which is optically coupled to the external cable 237 via the connector 230, transmits the light to the external cable 237. The light travels through the handpiece 236 to the distal tip 240 and is ultimately scanned across the FOV. Light reflected from the FOV is collected at the distal tip 240 and a representative signal is transmitted to the control module 224 using detection optical fibers or one or wavelengths of the reflected light may be converted to electrical signals and transmitted to the control module 224 using electrical wires.
In some embodiments, the representative signal transmitted to the control module 224 is an optical signal. Thus, a return signal line 266 may be an optical fiber or an optical fiber bundle that is coupled to the detector module 264 and transmit the representative optical signal to the detector module 264. At the detector module 264, the optical signals corresponding to the FOV characteristics are converted into electrical signals and returned to the real time processor 262 for real time processing and parsing to the video processor and controller 254. Electrical signals representative of the optical signals may be amplified and optionally digitized by the detector module 264 prior to transmission to real time processor 262. In an alternative embodiment, analog signals may be passed to the real time processor 262 and analog-to-digital conversion performed there. It is also contemplated that the detector module 264 and the real time processor 262 may be combined into a single physical element.
In other embodiments, reflected light representative of the FOV may be converted into electrical signals at the distal tip 240 or endoscope tip 242 by one or more photo-detectors such as PIN photodiodes, avalanche photodiodes (APDs), or photomultiplier tubes. In such an embodiment, the return line 266 may be electrical wires and the detector module 264 may be omitted.
Continuing with the description of the block diagram of the endoscope 220, the video processor and controller 254 has an interface 252 that may include several separate input/output lines. A video output may be coupled to the monitor 222 for displaying the image. A recording device 274 may also be coupled to the interface 252 to capture video information recording a procedure. Additionally, in some embodiments, the endoscope system 220 may be connected to a network or the Internet 278 for remote expert input, remote viewing, archiving, library retrieval, or the like. In another embodiment, the video processor and controller 254 may optionally combine data received via the interface 252 with image data and the monitor 222 with information derived from a plurality of sources including the distal tip 240.
In another embodiment, in addition to or as an alternative to the monitor 222, the image may be output to one or more remote devices such as, for example, a head mounted display. In such an embodiment, context information such as viewing perspective may be combined with FOV and/or other information in the video processor and controller 254 to create context-sensitive information display.
From the foregoing it will be appreciated that, although specific embodiments of the invention have been described herein for purposes of illustration, various modifications may be made without deviating from the spirit and scope of the invention. For example, the teachings disclosed herein are generally applicable for use in scanned beam imagers, and bar code scanners in addition to scanned beam endoscopes. Accordingly, the invention is not limited except as by the appended claims.
This application is based on provisional application No. 60/777,695, filed Feb. 27, 2006.
Number | Date | Country | |
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60777695 | Feb 2006 | US |