Not Applicable.
Advances in technology have provided advances in imaging capabilities for medical use. One area that has enjoyed some of the most beneficial advances is that of endoscopic surgical procedures because of the advances in the components that make up an endoscope.
Conventional endoscopes used in, e.g., arthroscopy and laparoscopy are designed such that the image sensors are placed at the proximal end of the device, within the hand-piece unit. In such a configuration, the endoscope unit must transmit the incident light along its length toward the sensor via a complex set of precisely coupled optical components, with minimal loss and distortion. The cost of the endoscope unit is dominated by the optics, since the components are expensive and the manufacturing process is labor intensive. Moreover, this type of scope is mechanically delicate and relatively minor impacts can easily damage the components or upset the relative alignments thereof. This necessitates frequent, expensive repair cycles in order to maintain image quality.
One solution to this issue is to place the image sensor within the endoscope itself at the distal end, thereby potentially approaching the optical simplicity, robustness and economy that are universally realized within, e.g., cell phone cameras. An acceptable solution to this approach is by no means trivial, however, as it introduces its own set of engineering challenges, not the least of which is the fact that the sensor must fit within a highly confined area.
Placing aggressive constraints on sensor area naturally pushes one in the direction of fewer and/or smaller pixels. Lowering the pixel count directly affects the spatial resolution. Reducing the pixel area reduces the available signal capacity and the sensitivity. Lowering the signal capacity reduces the dynamic range i.e. the ability of the camera to simultaneously capture all of the useful information from scenes with large ranges of luminosity. There are various methods to extend the dynamic range of imaging systems beyond that of the pixel itself. All of them have some kind of penalty however, (e.g. in resolution or frame rate) and they can introduce undesirable artifacts which become problematic in extreme cases. Reducing the sensitivity has the consequence that greater light power is required to bring the darker regions of the scene to acceptable signal levels. Lowering the F-number will compensate for a loss in sensitivity too, but at the cost of spatial distortion and reduced depth of focus.
With an image sensor located in the distal end of an endoscopic device, there are challenges present, which are not at issue when the imaging sensor is located remotely from the distal end of the endoscopic device. For example, when a user or operator rotates or changes the angle of the endoscopic device, which is common during a surgery, the image sensor will change orientation and the image horizon shown on screen will also change. What is needed are devices and systems that accommodate an image sensor being located in the distal end of the endoscopic device without changing the orientation and maintaining a constant image horizon for the user or operator. As will be seen, the disclosure provides devices and systems that can do this in an efficient and elegant manner.
Non-limiting and non-exhaustive implementations of the disclosure are described with reference to the following figures, wherein like reference numerals refer to like parts throughout the various views unless otherwise specified. Advantages of the disclosure will become better understood with regard to the following description and accompanying drawings where:
The disclosure extends to endoscopic devices and systems for image rotation for a rigidly coupled image sensor. The disclosure allows for a distal prism to rotate, which changes the angle of view of the user or operator, while the sensor remains fixed at a constant location. This allows the device to be used in the same manner as expected by a user or operator experienced in using conventional rigid endoscopy systems. The user or operator may rotate an outer lumen, thereby changing the angle of view, while the sensor remains in a fixed position and the image viewable on screen remains at a constant horizon. The prism may rotate while the sensor does not rotate, such that the user does not lose orientation.
In the following description of the disclosure, reference is made to the accompanying drawings, which form a part hereof, and in which is shown by way of illustration specific implementations in which the disclosure may be practiced. It is understood that other implementations may be utilized and structural changes may be made without departing from the scope of the disclosure.
It must be noted that, as used in this specification and the appended claims, the singular forms “a,” “an,” and “the” include plural referents unless the context clearly dictates otherwise.
As used herein, the terms “comprising,” “including,” “containing,” “characterized by,” and grammatical equivalents thereof are inclusive or open-ended terms that do not exclude additional, unrecited elements or method steps.
Further, where appropriate, functions described herein can be performed in one or more of: hardware, software, firmware, digital components, or analog components. For example, one or more application specific integrated circuits (ASICs) can be programmed to carry out one or more of the systems and procedures described herein. Certain terms are used throughout the following description and Claims to refer to particular system components. As one skilled in the art will appreciate, components may be referred to by different names. This document does not intend to distinguish between components that differ in name, but not function.
Referring now to the figures, it will be appreciated that
In one implementation, the handpiece 120 may comprise a body 122 that may be fixed relative and attached to an inner lumen 131 of the endoscopic device 130. The handpiece 120 may also comprise a spring loaded mechanism. The spring loaded mechanism may comprise a spring cap 124, which may be located adjacent the body 122. The spring cap 124 may be fixed and attached to the inner lumen 131 of the endoscope 130. At least one spring 126 may be present in the spring cap 124 and may be part of the spring loaded mechanism. This spring-loaded mechanism may function to maintain constant contact between a distal lens holder 148 and a proximal lens holder 144, discussed more fully below in relation to
It will be appreciated that the outer lumen 133 may be in mechanical communication with the handpiece 120. In an implementation, the outer lumen 133 may be spring-loaded at a junction with the handpiece 120 to provide consistent contact between the distal lens holder 148 and the proximal lens holder 144, thus ensuring consistent axial distance with the proximal lens elements 146 and the distal lens elements 147 and retaining focus while the outer lumen 133 rotates.
In an implementation, the handpiece 120 may comprise a focus mechanism. The focus mechanism may permit focal adjustments in the system and may be attached to the inner lumen 131, such that the inner lumen 131 is movable axially as the focus mechanism may function to control the axial distance between the proximal lens 146 and the distal lens 147. The focus mechanism may move the inner lumen 131 in the axial direction only and may not allow rotation.
The endoscopic device 130 may comprise a proximal portion 132, which may be defined as the portion nearest the handpiece 120, and a distal portion 134, which may be defined as the portion farthest away from the handpiece 120. The distal portion 134 may comprise a tip 136. The endoscopic device 130 may house the image sensor 140 for providing visualization of an area. In one implementation, the image sensor 140 may be located within the distal portion 134 at or near the tip 136 of the endoscopic device 130. The endoscopic device may also comprise the inner lumen 131 and the outer lumen 133. In one implementation, the image sensor 140 and the inner lumen 131 may be fixed relative to the outer lumen 133. In the implementation, the outer lumen 133 may be rotatable about an axis A-A of the endoscope 130 and with respect to the image sensor 140 and the inner lumen 131. Thus, the disclosure extends to any endoscopic device and system for use with a rigidly coupled image sensor 140.
Referring now to
The distal lens holder 148 may be rotatable with respect to the inner lumen 131. It will be appreciated that the outer lumen 133 may be freely rotatable, such that any components that are attached thereto may also be free to rotate. The distal lens holder 148 may be attached to the outer lumen 133 and is freely rotatable. The distal lens holder 148 may abut against an outer window 151. The outer window 151 may also be attached to the outer lumen 133 and may be rotatable relative to the inner lumen 131 and the image sensor 140. The outer window 151 may be in mechanical communication with the outer lumen 133 and may be located on the terminal end of the tip 136 of the endoscope 130.
The distal lens holder 148 may house a prism 145 and a distal lens 147, both of which may be located at or near the tip 136 of the endoscope 130. It should be noted that the prism 145 as shown in the Figures and referenced herein may be comprised of multiple elements as necessary to properly change the direction of light through the system. It should also be noted the proximal lens 146 and distal lens 147 as shown in the Figures and referenced herein together comprise a complete lens system that projects a focused image on the image sensor 140. The lens system may be comprised of multiple elements and any number of these elements may be included in the distal lens 147 with the remainder included in the proximal lens 146. The prism 145 and the distal lens 147 may both be fixed to the outer lumen 133 and may be rotatable relative to the inner lumen 131 and the image sensor 140, such that as the angle of view is changed the orientation of an image remains constant within the viewing area of the user. It will be appreciated that the distal lens holder 148 may comprise a guide for aligning the prism 145 and the distal lens 147 within the tip 136 of the endoscope 130. The distal lens holder 148 may be fixed to the outer lumen 133 and may be rotatable relative to the inner lumen 131 and the image sensor 140. The distal lens 147 may be located near the tip 136 of the endoscope 130 and the proximal lens 146 may be located proximally with respect to the distal lens 147. The proximal lens 146 may be fixed to the inner lumen 131, such that it remains fixed relative to the outer lumen 133 as the outer lumen 133 is rotated.
As illustrated in
The proximal lens holder 144 may comprise an inner guide wall 144a that is formed at one end of the proximal lens holder 144 and an outer guide wall 144b that is formed at the other end of the proximal lens holder 144. The proximal lens holder 144 acts as a housing and guide for aligning the proximal lens 146 with respect to the distal lens 147, wherein the proximal lens holder 144 is fixed to the inner lumen 131 and remains fixed relative to the outer lumen 133 as the outer lumen 133 is rotated. In an implementation, the inner guide wall 144a may engage the guide of the distal lens holder 148, such that the distal lens holder 148 is rotatable with respect to the proximal lens holder 144.
In one implementation, as illustrated in
As illustrated best in
Referring now to
Referring generally to the image sensor technology illustrated in
Typically CMOS image sensors include the circuitry necessary to convert the image information into digital data and have various levels of digital processing incorporated thereafter. This can range from basic algorithms for the purpose of correcting non-idealities, which may, for example, arise from variations in amplifier behavior to full image signal processing (ISP) chains, providing video data in the standard sRGB color space (cameras-on-chip).
The desired degree of sensor complexity for a given camera system is driven by several factors, one of which is the available physical space for the image sensor. The most extreme functionally minimal CMOS sensor would have only the basic pixel array plus a degree of buffering to drive the analog data off chip. All of the timing signals required to operate and read out the pixels would be provided externally. The need to supply the control signals externally adds many pads, which consume significant real estate, however. Therefore it doesn't necessarily follow that minimal functionality equates to minimal area.
If the second stage is an appreciable distance from the sensor, it becomes much more desirable to transmit the data in the digital domain, since it is rendered immune to interference noise and signal degradation. There is a strong desire to minimize the number of conductors since that reduces the number of pads on the sensor (which consume space), plus the complexity and cost of camera manufacture. Although the addition of analog to digital conversion to the sensor is necessitated, the additional area is offset to a degree, owing to a significant reduction in the required analog buffering power. In terms of area consumption, given the typical feature size available in computer information systems technologies, it is preferable to have all of the internal logic signals be generated on chip via a set of control registers and a simple command interface.
The disclosure contemplates and covers aspects of a combined sensor and system design that allows for high definition imaging with reduced pixel counts in a highly controlled illumination environment. This is accomplished by virtue of frame by frame pulsed color switching at the light source in conjunction with high frames capture rates and a specially designed monochromatic sensor. Since the pixels are color agnostic, the effective spatial resolution is appreciably higher than for their color (usually Bayer-pattern filtered) counterparts in conventional single-sensor cameras. They also have higher quantum efficiency since far fewer incident photons are wasted. Moreover, Bayer based spatial color modulation requires that the modulation transfer function (MTF) of the accompanying optics be lowered compared with the monochrome case, in order to blur out the color artifacts associated with the Bayer pattern. This has a detrimental impact on the actual spatial resolution that can be realized with color sensors.
The disclosure is also concerned with a system solution for endoscopy applications in which the image sensor is resident at the distal end of the endoscope. In striving for a minimal area sensor based system, there are other design aspects that can be developed too, beyond the obvious reduction in pixel count. In particular, the area of the digital portion of the chip should be minimized, as should the number of connections to the chip (pads). This involves the design of a full-custom CMOS image sensor with several novel features.
It will be appreciated that the disclosure may be used with any image sensor, whether a CMOS image sensor or CCD image sensor, without departing from the scope of the disclosure. Further, the image sensor may be located in any location within the overall system, including, but not limited to, the tip of the endoscope, the hand piece of the imaging device or camera, the control unit, or any other location within the system without departing from the scope of the disclosure.
Implementations of an image sensor that may be utilized by the disclosure include, but are not limited to, the following, which are merely examples of various types of sensors that may be utilized by the disclosure.
Referring now to
It will be appreciated that the teachings and principles of the disclosure may be used in a reusable device platform, a limited use device platform, a re-posable use device platform, or a single-use/disposable device platform without departing from the scope of the disclosure. It will be appreciated that in a re-usable device platform an end-user is responsible for cleaning and sterilization of the device. In a limited use device platform the device can be used for some specified amount of times before becoming inoperable. Typical new device is delivered sterile with additional uses requiring the end-user to clean and sterilize before additional uses. In a re-posable use device platform a third-party may reprocess the device (e.g., cleans, packages and sterilizes) a single-use device for additional uses at a lower cost than a new unit. In a single-use/disposable device platform a device is provided sterile to the operating room and used only once before being disposed of.
Additionally, the teachings and principles of the disclosure may include any and all wavelengths of electromagnetic energy, including the visible and non-visible spectrums, such as infrared (IR), ultraviolet (UV), and X-ray.
The foregoing description has been presented for the purposes of illustration and description. It is not intended to be exhaustive or to limit the disclosure to the precise form disclosed. Many modifications and variations are possible in light of the above teaching. Further, it should be noted that any or all of the aforementioned alternate implementations may be used in any combination desired to form additional hybrid implementations of the disclosure.
Further, although specific implementations of the disclosure have been described and illustrated, the disclosure is not to be limited to the specific forms or arrangements of parts so described and illustrated. The scope of the disclosure is to be defined by the claims appended hereto, any future claims submitted here and in different applications, and their equivalents.
This application claims the benefit of U.S. Provisional Application No. 61/791,629, filed Mar. 15, 2013, which is hereby incorporated by reference herein in its entirety, including but not limited to those portions that specifically appear hereinafter, the incorporation by reference being made with the following exception: In the event that any portion of the above-referenced provisional application is inconsistent with this application, this application supersedes said above-referenced provisional application.
Number | Date | Country | |
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61791629 | Mar 2013 | US |