Scope sensing in a light controlled environment

Abstract

The disclosure extends to methods, systems, and computer program products for detecting whether an illumination source of an endoscope is in use (inside the body of a patient) versus not in use (outside the body of a patient). The disclosure relies on the fact that the working environment is lit solely by the endoscope and its components. Thus, communication between the illumination or light source controller and the imaging device, such as a surgical camera, is required. When the illumination or light source is turned off and the endoscope is outside the body, a sensor will detect ambient light alerting the illumination source controller that it is outside the body, which then keeps the illumination source off or at a low intensity level. Conversely, when the illumination source is turned off and the endoscope is inside the body, the sensor will not detect any light (or will detect only a very low level of light). Based on this logic, if the imaging device, such as a camera, knows that the light is off during a specific period of time the frame(s) from that time period can be analyzed and the level of light gathered in the frame(s) will show the scope location either inside or outside of the body.

Description

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

Not Applicable.

BACKGROUND

Current minimally invasive surgical procedures rely on endoscopes for visualization of the surgical site. In the arthroscopy, laparoscopy, urology, gynecology, and ENT (ear, nose, and throat) specialties, rigid endoscopes are primarily used. A rigid endoscope is constructed of an inner lumen containing multiple glass lens elements for visualization and an outer lumen containing a bundle of fiber optic strands for carrying light from a light source to the surgical site.

Conventional surgical light systems are very inefficient. From the light engine, which is typically a metal halide bulb, halogen bulb, xenon bulb, or LED(s) (light emitting diode), to the surgical site over ninety-five percent of the light is lost. These losses occur at multiple locations, the first being at the optic placed in front of the light engine to gather the light from a wide dispersion angle and focus it into a collimated beam with a diameter small enough to transmit to a fiber optic light cable. The second loss point is the junction of the focusing optic and the aforementioned fiber optic light cable. The fiber optic light cable is a bundle, typically with a diameter of five millimeters, of small fiber optic strands and measures one to three meters in length. The third loss point is over the length of the fiber bundle due to the attenuation rate of the bulk fiber strands. The fiber optic light cable transmits light from the light source to the endoscope in sterile field. The fourth loss point is the junction between the light cable and the proximal end of the endoscope.

Due to the losses in the light transmission path, the light source must generate a significant amount of light. This results in a significant amount of heat generated, particularly at each of the junction points and at the distal tip of the scope. The heat generated, specifically at the distal scope tip and at the junction between the light cable and scope, can present a safety risk to the surgical patient. The heat is such that if the scope is inadvertently rested on the patient for a period of time, a burn can occur. This is an issue with all conventional light sources and every year a few such incidents occur and are reported to the FDA (Food and Drug Administration).

BRIEF DESCRIPTION OF THE DRAWINGS

Non-limiting and non-exhaustive implementations of the present 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 present disclosure will become better understood with regard to the following description and accompanying drawings where:

FIG. 1 illustrates a flow chart of an example method for controlling power to an endoscopic light source in a light controlled environment according to one implementation;

FIG. 2 illustrates an imaging device located outside of a light deficient environment, such as a patient's body, wherein the light source is turned off due to the amount of ambient light present in accordance with the system and method described herein;

FIG. 3 illustrates an imaging device located in a light deficient environment, such as a patient's body, wherein the light source is turned on due to the lack of ambient light present in accordance with the system and method described herein;

FIG. 4 illustrates a light threshold value and comparison chart of an example method according to one implementation;

FIG. 5 illustrates an interval in a constant light system and a pulsed light system wherein a frame is captured for analysis in accordance with the system and method described herein;

FIG. 6 illustrates a system for controlling power to an endoscopic light source in a light controlled environment according to one implementation;

FIGS. 7A and 7B illustrate a perspective view and a side view, respectively, of an implementation of a monolithic sensor having a plurality of pixel arrays for producing a three dimensional image in accordance with the teachings and principles of the disclosure;

FIGS. 8A and 8B illustrate a perspective view and a side view, respectively, of an implementation of an imaging sensor built on a plurality of substrates, wherein a plurality of pixel columns forming the pixel array are located on the first substrate and a plurality of circuit columns are located on a second substrate and showing an electrical connection and communication between one column of pixels to its associated or corresponding column of circuitry; and

FIGS. 9A and 9B illustrate a perspective view and a side view, respectively, of an implementation of an imaging sensor having a plurality of pixel arrays for producing a three dimensional image, wherein the plurality of pixel arrays and the image sensor are built on a plurality of substrates.

DETAILED DESCRIPTION

The disclosure extends to methods, systems, and computer program products for detecting whether an endoscopic illumination or light source is in use (inside the body of a patient) versus not in use (outside the body of a patient). The methods, systems and computer program products rely on the fact that the working environment is lit solely by the endoscope and its components. Thus, communication between the illumination or light source controller and the imaging device, such as a surgical camera, is required. In the following description of the present 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 present 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.

For safety and power consumption reasons, what is needed are methods and systems for detecting when an illumination or light source is in use and when it is not in use. As will be seen, the disclosure provides methods and systems that can do this in an efficient and elegant manner.

Referring now to the figures, it will be appreciated that the disclosure relates to a detection mechanism for operating the illumination source when an endoscope is in use (inside the body of a patient) versus not in use (outside the body of a patient). The disclosure relies on the fact that the working environment is lit solely by the endoscope and its components. Thus, communication between the illumination or light source controller and the imaging device, such as a surgical camera, is required.

For safety reasons it is preferable to have the light source off while the endoscope is not in use. This removes the risk of burning a patient if, for example, the user inadvertently leaves the endoscope resting on the patient while performing other tasks. Every year there are reported cases of patient burns resulting from such misuse of conventional endoscopic video systems.

When the light is turned off and the endoscope is outside the body, the sensor will detect ambient light. Conversely, when the light is turned off and the endoscope is inside the body, the sensor will not detect any light (or will detect only a very low level of light). Based on this logic, if the camera knows that the light is off during a specific period of time the frame(s) from that time period can be analyzed and the level of light gathered in the frame(s) will show the scope location.

Knowing the location of the scope (inside or outside the body) allows the system to keep the light source off while outside the body and only turn the light source on when the endoscope is put into the body for use.

Alternately, the light source output intensity can be reduced to a low, safe level while the scope is outside the body and then increased to a high level when inside the body and in use. This implementation may be preferred for usability reasons. Users who are not familiar with the system described herein may suspect a functional problem with the system if the light source is completely off while the scope is not in use.

Referring now to FIG. 1, there is illustrated a method for controlling power to an endoscopic light source in a light controlled environment. As illustrated in the figure, at 110 the method may comprise sending an electric communication signal from an imaging device controller to a light source controller at a specified interval. It will be appreciated that the signal may be an instruction to turn off the light source for a predetermined sample period during which a single sample frame or a plurality of sample frames may be collected from an image sensor. At 120, the imaging device controller may receive a communication or data from the image sensor. Data may be collected from the image sensor for a single frame or a plurality of frames obtained during the predetermined sample period. The data may be related to an amount of ambient light received by the image sensor. At 130, the imaging device controller may analyze the sample frame or plurality of frames against a predetermined or predefined light threshold value. Analyzing the single frame or plurality of frames obtained during the predetermined sample period against a specified, predetermined threshold value is also illustrated in FIG. 4. The operation of the light source may be controlled based on the data received from the image sensor.

At 140, a determination is made by the image device controller. If the ambient light is above or below the predetermined light threshold value, then one of two processes may be followed. Specifically, if the measured light from the image sensor is determined to be below the predetermined light threshold value, then at 150 it is determined that the image sensor is in a light deficient environment. When it is determined that the light source is in a light deficient environment, that determination signifies that the imaging device is in-use. At 152, the light source remains in an operable state, thereby providing light to the light deficient environment. At 154, the light source may be turned off for a predetermined sample period and the process starts over again.

At 140, if the measured light from the image sensor is determined to be above the predetermined light threshold value, then at 160 it is determined that the image sensor is not in-use because it is outside of a light deficient environment. In such a circumstance, at 162, the light source is turned off, thereby providing a safety mechanism for controlling power to the light source. It will be appreciated that in one implementation, at 164, the turned off state may be a complete power down of the light source. In another implementation, at 166, the turned off state may be a reduction in power to the light source, such that the light source is only emitting a small amount of light energy. As noted previously, the method may include sampling at a plurality intervals, such as a second interval, to determine whether data received from the image sensor regarding a single frame is above or below the predetermined light threshold value.

Referring now to FIGS. 2 and 3, it will be appreciated that in one implementation, the default mode when the endoscopic light source system starts-up is for the light source to be turned off or in an off state. At this time, the imaging device controller is in communication with the light source controller and knows the light source is turned off or in an off state. At specified intervals, such as for example every 30^th frame, the imaging device captures a single frame and analyzes the light level against the predetermined light threshold value. It is to be understood that the specified intervals may be at any frequency that produces the desired functional result. Further, it is to be understood that the light threshold value may be defined as an amount of total light received by the image sensor; or the threshold value may be defined as an average of an amount of light received per pixel on the image sensor.

If the light source is determined to be not in-use as illustrated in FIG. 2, then the imaging device controller communicates information, instructions or data to the light source controller to remain off or in an off state. Conversely, if the light source is determined to be in-use as illustrated in FIG. 3, then the imaging device controller communicates information, instructions or data to the light source controller to turn on. Once the light source is turned on, a new pattern begins. Thus, at predetermined, specified intervals the light source is turned off for a predetermined sample period during which time the imaging device captures a single frame and analyzes the light level against the predetermined threshold value. It is understood that the sample period may be any length that is long enough for the imaging device to capture one frame, but short enough that is does not negatively affect video quality or user experience. As illustrated best in FIG. 4, if the data received from the image sensor is below the predetermined threshold value, then the imaging device recognizes the light source as being in-use in a light deficient environment, and the imaging device controller communicates with the light source controller to turn on. Whereas, if the data received from the image sensor is above the predetermined threshold value, then the image device recognizes the light source as being not-in-use and is outside the light deficient environment, and the imaging device controller communicates with the light source controller to remain off.

Referring now to FIG. 5, the light source may be a pulsed light system. In an implementation, the light in the pulsed light system may be obtained from laser light. In an implementation, the light in the pulsed light system may be obtained from one or more light emitting diodes. In another implementation, the light source may be a constant light system.

It will be appreciated that the sampling interval may be every 30^th frame as described above, or it may be any other frequency that provides the desired results. It is within the scope of the disclosure for the interval frequency may be different during the “in-use” condition and the “not-in-use” condition.

In an implementation, the imaging device, such as a camera, may provide constant control over the light source. In an implementation, the light source may have a default state that is changed by the imaging device as required.

The method and system of the disclosure may require communication between the light source controller and the imaging device controller. The disclosure also contemplates use of a light source with a response time that is fast enough that the “off” pulse during the sample period, during the “in-use” condition, does not adversely affect the video quality. LED and laser light sources may be used, while a metal halide bulb, halogen bulb, or xenon bulb may not be used in this implementation.

During use, the light source can be kept on constantly with a periodic “off” pulse or the light source can be pulsed “on” during normal use, illustrated best in FIG. 5, with an “on” pulse skipped for the black frame analysis.

In an implementation, the light intensity level can be reduced to a predetermined safe level while in the “not-in-use” state. In this implementation the default mode on startup could be a low light intensity level that poses no risk of burning. Then, as previously described, at predetermined intervals the light is turned off for the sample period and this sample frame is analyzed. If the result is “not-in-use”, the light is turned back on at the previous safe level and the pattern repeats. If the result is “in-use”, the light is turned on at the higher functional level.

In an implementation, the light could be pulsed light of a particular colors (including, but not limited to, RBG or YCbCr) rather than white light. In this implementation it may be desirable to change from pulsed colored light while “in-use” to pulsed or constant white light while “not-in-use” using the same techniques previously described. The default mode on startup could be a low level of pulsed or constant white light. Then, as previously described, at predetermined intervals the light is turned off for the sample period and this sample frame is analyzed. If the result is “not-in-use”, the white light is turned back on at the previous safe level and the pattern repeats. If the result is “in-use”, the pulsed color pattern is initiated.

In an implementation, the system may be comprised of a light source that is kept in a constant on-state with a mechanical shutter providing the periodic black frame. This shutter may be controlled by the imaging device, such that there would be no imaging device control of the light source needed. This shutter could be placed at any interface in the light path from the source to the distal tip of the endoscope. In this implementation there is no restriction on light source technology because there is no requirement for the light source to have a fast response time. Instead, the mechanical shutter requires a response time that is fast enough that the “off” pulse during the sample period, during the “in-use” condition, does not adversely affect the video quality.

In any implementation, a visual or audible signal could be given to inform the user of whether the system is in the “in-use” or “not-in-use” state. Alternately, the signal could inform the user when the state changes from “in-use” to “not-in-use” or from “not-in-use” to “in-use” or both.

A black frame would disrupt the video output. During image processing, the black frame can be removed and the previous frame can be displayed in its place. Conversely, multiple frames before and/or after the black frame can be used to construct a substitute frame.

Referring now to FIG. 6, a system for controlling power to an endoscopic light source in a light controlled environment is illustrated. The system may comprise an imaging device 200 comprising an imaging device controller 220, a light source comprising a light source controller 230; and an image sensor 240. It will be appreciated that the imaging device controller may cause the system to perform the following processes: send an electric communication signal to a light source controller at a specified interval; turn off the light source for a predetermined sample period based on the electric communication signal; collect data from the image sensor for a single frame obtained during the predetermined sample period, wherein the data relates to an amount of ambient light received by the image sensor; analyze the single frame obtained during the predetermined sample period against a specified, predetermined threshold value; and control the operation of the light source based on the data received from the image sensor.

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 FIGS. 7A and 7B, the figures illustrate a perspective view and a side view, respectively, of an implementation of a monolithic sensor 700 having a plurality of pixel arrays for producing a three dimensional image in accordance with the teachings and principles of the disclosure. Such an implementation may be desirable for three dimensional image capture, wherein the two pixel arrays 702 and 704 may be offset during use. In another implementation, a first pixel array 702 and a second pixel array 704 may be dedicated to receiving a predetermined range of wave lengths of electromagnetic radiation, wherein the first pixel array 702 is dedicated to a different range of wave length electromagnetic radiation than the second pixel array 704.

FIGS. 8A and 8B illustrate a perspective view and a side view, respectively, of an implementation of an imaging sensor 800 built on a plurality of substrates. As illustrated, a plurality of pixel columns 804 forming the pixel array are located on the first substrate 802 and a plurality of circuit columns 808 are located on a second substrate 806. Also illustrated in the figure are the electrical connection and communication between one column of pixels to its associated or corresponding column of circuitry. In one implementation, an image sensor, which might otherwise be manufactured with its pixel array and supporting circuitry on a single, monolithic substrate/chip, may have the pixel array separated from all or a majority of the supporting circuitry. The disclosure may use at least two substrates/chips, which will be stacked together using three-dimensional stacking technology. The first 802 of the two substrates/chips may be processed using an image CMOS process. The first substrate/chip 802 may be comprised either of a pixel array exclusively or a pixel array surrounded by limited circuitry. The second or subsequent substrate/chip 806 may be processed using any process, and does not have to be from an image CMOS process. The second substrate/chip 806 may be, but is not limited to, a highly dense digital process in order to integrate a variety and number of functions in a very limited space or area on the substrate/chip, or a mixed-mode or analog process in order to integrate for example precise analog functions, or a RF process in order to implement wireless capability, or MEMS (Micro-Electro-Mechanical Systems) in order to integrate MEMS devices. The image CMOS substrate/chip 802 may be stacked with the second or subsequent substrate/chip 806 using any three-dimensional technique. The second substrate/chip 806 may support most, or a majority, of the circuitry that would have otherwise been implemented in the first image CMOS chip 802 (if implemented on a monolithic substrate/chip) as peripheral circuits and therefore have increased the overall system area while keeping the pixel array size constant and optimized to the fullest extent possible. The electrical connection between the two substrates/chips may be done through interconnects 803 and 805, which may be wirebonds, bump and/or TSV (Through Silicon Via).

FIGS. 9A and 9B illustrate a perspective view and a side view, respectively, of an implementation of an imaging sensor 900 having a plurality of pixel arrays for producing a three dimensional image. The three dimensional image sensor may be built on a plurality of substrates and may comprise the plurality of pixel arrays and other associated circuitry, wherein a plurality of pixel columns 904a forming the first pixel array and a plurality of pixel columns 904b forming a second pixel array are located on respective substrates 902a and 902b, respectively, and a plurality of circuit columns 908a and 908b are located on a separate substrate 906. Also illustrated are the electrical connections and communications between columns of pixels to associated or corresponding column of circuitry.

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.

Claims

1. A method for controlling power to an endoscopic light source in a light controlled environment comprising: sending an electric communication signal from an imaging device controller to a light source controller at a specified interval;turning off a light source for a predetermined sample period based on the electric communication signal;collecting data from an image sensor for a single frame obtained during the predetermined sample period, wherein the data relates to an amount of ambient light received by the image sensor while the light source is turned off, such that there is no light received from the light source during the predetermined sample period;analyzing the single frame obtained during the predetermined sample period against a specified, predetermined threshold value; andcontrolling the operation of the light source based on the data received from the image sensor, such that control and operation of the light source is dependent upon the amount of electromagnetic radiation received by the image sensor during the predetermined sample period when the light source is turned off, wherein controlling the operation of the light source comprises: setting a light intensity for the light source at or below a predetermined level to reduce heat that is generated at a distal scope tip and at a junction between a light cable and a scope due to light losses in a light transmission path in response to determining that the amount of ambient light is above the predetermined threshold value for the single frame.

2. The method of claim 1, wherein the light source remains in an operable state to thereby provide light to the light deficient environment when the data received from the image sensor is below the predetermined threshold value.

3. The method of claim 1, wherein setting the light intensity for the light source at or below the predetermined level comprises turning off the light source, thereby providing a safety mechanism for controlling power to the light source.

4. The method of claim 3, wherein the turned off state is a complete power down of the light source.

5. The method of claim 3, wherein the turned off state is a reduction in power to the light source.

6. The method of claim 1, wherein the method further comprises periodically sampling at a second interval to determine whether data received from the image sensor is above or below the predetermined threshold value when the light source is off.

7. The method of claim 1, wherein a default mode when the endoscopic light source system starts up is for the light source to be turned off.

8. The method of claim 7, wherein the imaging device controller is in communication with the light source controller.

9. The method of claim 8, wherein at specified intervals the imaging device captures the single frame and analyzes the light level against the predetermined threshold value.

10. The method of claim 9, wherein the predetermined threshold value is an amount of total light received by the image sensor.

11. The method of claim 9, wherein the predetermined threshold value is an average of an amount of light received per pixel.

12. The method of claim 7, wherein if the light source is determined to be not in-use then the imaging device controller communicates to the light source controller to remain off.

13. The method of claim 7, wherein if the light source is determined to be in-use then the imaging device controller communicates to the light source controller to turn on, wherein the light intensity for the light source is above the predetermined level.

14. The method of claim 13, wherein once the light source is turned on, a new sampling pattern begins, such that at predetermined, specified intervals the light source is turned off for a predetermined sample period, the imaging device captures a single frame, and analyzes the light level against the predetermined threshold value.

15. The method of claim 14, wherein if the data received from the image sensor is below the predetermined threshold value, then the imaging device recognizes the light source as being in-use in a light deficient environment, and the imaging device controller communicates with the light source controller to turn on.

16. The method of claim 14, wherein if the data received from the image sensor is above the predetermined threshold value, then the image device recognizes the light source as being not-in-use and is outside the light deficient environment, and the imaging device controller communicates with the light source controller to remain off.

17. The method of claim 1, wherein the light source is a pulsed light system.

18. The method of claim 17, wherein the light in the pulsed light system is obtained from laser light.

19. The method of claim 17, wherein the light in the pulsed light system is obtained from one or more light emitting diodes.

20. The method of claim 17, wherein the light in the pulsed light system comprises a variety of specific colors.

21. The method of claim 20, wherein if the light received by the image sensor is above the predetermined threshold value, then the light source is recognized as being not in-use and is outside of a light deficient environment.

22. The method of claim 21, wherein the light output is changed to pulsed white light at a low intensity level, the low intensity level at or below the predetermined level.

23. The method of claim 1, wherein the light source is a constant light system.

24. The method of claim 1, wherein the frequency of the interval at which data is sampled is different during an in use condition than during a not in use condition.

25. The method of claim 1, wherein a default mode when the endoscopic light source system starts up is for the light source to be turned on.

26. The method of claim 25, wherein at predetermined, specified intervals the imaging device controller communicates with the light source controller to turn off the light source for a predetermined sample period, the imaging device captures a single frame and analyzes the light level against the predetermined threshold value.

27. The method of claim 26, wherein if the data received from the image sensor is below the predetermined threshold value, then the imaging device recognizes the light source as being in-use in a light deficient environment, and the imaging device controller communicates with the light source controller to return to the default mode.

28. The method of claim 26, wherein if the data received from the image sensor is above the predetermined threshold value, then the image device recognizes the light source as being not-in-use and is outside the light deficient environment, and the imaging device controller communicates with the light source controller to remain off.

29. The method of claim 1, wherein the controller communicating with the system provides a user with information regarding the current state of the system.

30. The method of claim 29, wherein the information is provided visually.

31. The method of claim 29, wherein the information is provided audibly.

32. The method of claim 1, wherein the controller communicating with the system provides a user with information regarding a change in the state of the system.

33. The method of claim 32, wherein the information is provided visually.

34. The method of claim 32, wherein the information is provided audibly.

35. A method for operation of an endoscopic light source, the method comprising: sending an electric communication signal from an imaging device controller to a light source controller at a specified interval;turning off a light source for a predetermined sample period based on the electric communication signal;collecting data from an image sensor for a single frame obtained during the predetermined sample period, wherein the data relates to an amount of ambient light received by the image sensor while the light source is turned off, such that there is no light received from the light source during the predetermined sample period;determining that the amount of ambient light is above a predetermined threshold value based on the single frame; andsetting a light intensity for the light source at or a below a predetermined level to reduce heat that is generated at a distal scope tip and at a junction between a light cable and a scope due to light losses in a light transmission path.