Electronic endoscope system

Abstract

One aspect of the present invention is an electronic endoscope system comprising a processor and a light source module having a light emitting element. The light source module includes a first storage device for storing a reference light quantity value, of the light emitting element under a predetermined condition, obtained by the light source module alone. The processor includes a second storage device and a control unit. The control unit: writes, to the second storage device, the reference light quantity value read from the first storage device after the light source module is installed; compares a start-time light quantity value, which is the reference light quantity value of the light emitting element acquired under the predetermined condition when the system is started, and each of the first light quantity value, which is the reference light quantity value read from the first storage device, and a second light quantity value, which is the reference light quantity value read from the second storage device; and determines which of the first storage device and the second storage device has more reliable data on the basis of the result of comparison.

Description

Electronic Endoscope System

[0001] The present invention relates to an electronic endoscope system configured to perform imaging of biological tissue.

[0002] In the field of medical devices, an endoscope system is known that can generate images suitable for diagnosing lesions hidden within a body cavity by illuminating biological tissue within the body cavity and capturing an image of the illuminated biological tissue within the body cavity as a subject. Conventionally, lamp light sources such as xenon lamps and halogen lamps that emit white light have been used as illumination light, but recently, light source modules including light emitting diodes (LEDs) that emit light in a specific wavelength band have been used instead of lamp light sources (e.g., International Publication No. 2016 / 056476).

[0003] Since the output characteristics of light emitted from a light source are generally nonlinear, the output characteristics of the light source are measured in advance using a calibration device, and correction coefficients for linearly correcting the output characteristics are recorded in a nonvolatile memory. When the light source module is used, the output characteristics of the emitted light are linearly corrected using the recorded correction coefficients.

[0004] Using a highly durable storage device (memory) as a non-volatile memory for storing correction coefficients for correcting the output characteristics of the light source increases the system's cost, making it undesirable. On the other hand, if a highly durable storage device is not used and the data stored in the storage device is lost, it is necessary to measure the output characteristics of the light source again using calibration equipment to determine the correction coefficients. This measurement requires a lot of man-hours, making the recalibration process cumbersome. Even when replacing the light source module itself, a calibration process for the new light source module is required, which is also cumbersome.

[0005] Therefore, an object of the present invention is to ensure the robustness of data when data for correcting the output characteristics of a light source is stored in a storage device in an electronic endoscope system without using a highly durable storage device.

[0006] One aspect of the present disclosure is an electronic endoscope system configured to capture images of biological tissue, comprising: a processor for processing captured images of the biological tissue; and a light source module that is installable in the electronic endoscope processor and generates illumination light for the biological tissue based on light emitted from at least one light-emitting element. The light source module includes a first storage device that stores a correction coefficient for correcting output characteristics of the light-emitting element and a reference light intensity value of the light-emitting element under predetermined conditions, the correction coefficient being obtained before the light source module is installed in the processor. The processor includes a second storage device, a photodetector that detects the light intensity of the light-emitting element, and a control unit. After the light source module is incorporated into the processor, the control unit writes the correction coefficient and the reference light intensity value read from the first storage device to the second storage device, and at system startup, compares the startup light intensity value, which is the reference light intensity value of the light-emitting element obtained under the specified conditions, with each of the first light intensity value, which is the reference light intensity value read from the first storage device, and the second light intensity value, which is the reference light intensity value read from the second storage device, and determines which of the data stored in the first storage device and the second storage device is more likely based on the comparison result.

[0007] The control unit may determine that the light source module is faulty if the difference between the startup light intensity value and the first light intensity value is greater than a predetermined threshold value and the difference between the startup light intensity value and the second light intensity value is greater than a predetermined threshold value.

[0008] The control unit may determine that the data stored in the second storage device is more likely to be reliable than the data stored in the first storage device if the difference between the startup light intensity value and the first light intensity value is greater than a predetermined threshold and the difference between the startup light intensity value and the second light intensity value is less than a predetermined threshold.

[0009] When the control unit determines that the data stored in the second storage device is more likely, the control unit may overwrite the data read from the second storage device onto the first storage device.

[0010] The control unit may determine that the data stored in the first storage device is more likely to be reliable than the data stored in the second storage device if the difference between the startup light intensity value and the first light intensity value is less than a predetermined threshold and the difference between the startup light intensity value and the second light intensity value is greater than a predetermined threshold.

[0011] When the control unit determines that the data stored in the first storage device is more likely, the control unit may overwrite the data read from the first storage device with the data stored in the second storage device.

[0012] According to the above-described electronic endoscope system, when data for correcting the output characteristics of the light source is stored in a storage device in the electronic endoscope system, the robustness of the data can be ensured without using a highly durable storage device.

[0013] 1 is a block diagram showing an example of the configuration of an electronic endoscope system of an embodiment. FIG. 2 is a block diagram focusing on parts related to light source control in the electronic endoscope system of an embodiment. FIG. 3 is a diagram showing the configuration when calibrating an LED in the electronic endoscope system of an embodiment. FIG. 4 is a diagram illustrating an example of the relationship between the duty ratio and illuminance of a PWM signal applied to an LED before and after correction. FIG. 5 is a diagram showing an example of data processing for a memory when calibrating a light source module. FIG. 6 is a diagram showing an example of data processing for a memory when incorporating a light source module into a processor. FIG. 7 is a flowchart showing the startup process of an electronic endoscope system of an embodiment. FIG. 8 is a flowchart showing the startup process of an electronic endoscope system of an embodiment. FIG. 9 is a diagram showing an example of data processing for a memory when replacing a light source module. FIG. 10 is a diagram showing an example of data processing for a memory when data in the memory of the light source module is lost.

[0014] The electronic endoscope system of this embodiment will be described in detail below with reference to the drawings. Fig. 1 is a block diagram showing an example of the configuration of an electronic endoscope system 1 of this embodiment. As shown in Fig. 1, the electronic endoscope system 1 is a system specialized for medical use, and includes an electronic scope (endoscope) 10, an electronic endoscope processor 20 (hereinafter simply referred to as "processor 20") to which the electronic scope 10 is connected via a connector, and a monitor 40.

[0015] The processor 20 includes a control unit 21. The control unit 21 has a CPU that executes various programs stored in a memory 23 and comprehensively controls the entire electronic endoscope system 1. The control unit 21 is also connected to an operation panel 24. The control unit 21 changes each operation of the electronic endoscope system 1 and parameters for each operation in response to instructions from the surgeon input to the operation panel 24. The control unit 21 supplies clock pulses, which serve as a reference for the timing of each operation of each part in the electronic endoscope system 1, to each part in the system.

[0016] The processor 20 is provided with a light source module 30. The light source module 30 includes a light-emitting device (LED) that emits illumination light for illuminating a subject, such as biological tissue within a body cavity. When a single LED is used, the LED is preferably a white LED. Although not shown, multiple LEDs may be provided. The multiple LEDs each emit light with a different wavelength band. For example, the multiple LEDs include a UV LED, a blue LED, a green LED, an amber LED, and a red LED. The illumination light is white light or pseudo-white light obtained by combining the light emitted from the multiple LEDs. White light is light with a flat spectral intensity distribution in the visible light band, while pseudo-white light is light with a non-flat spectral intensity distribution that is a mixture of light from multiple wavelength bands. The illumination light from the light source module 30 is focused on the incident end face of a light carrying bundle (LCB) 11 provided in the electronic endoscope 10 and enters the LCB 11. Furthermore, the illumination light emitted from the exit end face of the LCB 11 is irradiated onto the subject via a light distribution lens 12. Return light from the subject illuminated by the illumination light from the light distribution lens 12 forms an optical image on the light receiving surface of an image sensor 14 via an objective lens 13.

[0017] During manufacturing of the light source module 30, calibration is performed on each of one or more LEDs of the light source module 30, as described below. Calibration is a process for ensuring the linearity of the LEDs. Known LED dimming methods include PWM dimming and analog dimming. PWM dimming is a method for adjusting the illuminance of an LED by adjusting the duty ratio of a PWM signal, while analog dimming is a method for adjusting the illuminance of an LED by changing the amount of current supplied to the LED. In either dimming method, the relationship between the illuminance of the LED and the input, such as the duty ratio or current of the PWM signal, is not linear in an LED before calibration. Therefore, the purpose of calibration is to set a correction coefficient for adjusting this relationship to become linear.

[0018] The light source module 30 is configured to be mountable in a housing (not shown) of the processor 20. When the light source module 30 is manufactured, calibration is performed for each of the one or more LEDs, and then the calibrated light source module 30 is mounted in the processor 20. Furthermore, if the light source module 30 breaks down or deteriorates over time, a new light source module 30 can be mounted in the processor 20 after calibration.

[0019] The image sensor 14 is an image sensor with a Bayer pixel arrangement. The image sensor 14 accumulates and reads an optical image formed by each pixel on the light receiving surface as an electric charge according to the amount of light, and generates and outputs image data. The image sensor 14 may be a CMOS image sensor, a CCD image sensor, or any other type of imaging device. The image sensor 14 may also be equipped with a complementary color filter.

[0020] The electronic scope 10 includes a signal processing unit 15 in a connection with the processor 20. Under the control of the control unit 21, the signal processing unit 15 drives the image sensor 14 and acquires image data from the image sensor 14. In one embodiment, the signal processing unit 15 supplies a one-frame synchronization signal (e.g., a vertical synchronization signal) to the image sensor 14, acquires image data of the subject from the image sensor 14 on a frame-by-frame basis, and transmits the data to the image processing unit 22 of the processor 20. The frame period is, for example, 1 / 30 or 1 / 60 seconds. Note that the signal processing unit 15 is not limited to supplying a one-frame synchronization signal. Some image sensors may transmit image data based on a synchronization signal they create themselves. In such cases, the signal processing unit 15 does not need to supply a one-frame synchronization signal to the image sensor.

[0021] The image processing unit 22 of the processor 20 buffers the imaging data output from the signal processing unit 15 and performs predetermined image processing on the imaging data, and then generates a video format signal and outputs it to the monitor 40. Examples of image processing include demosaic processing, matrix calculation, and edge enhancement processing.

[0022] Next, a description will be given of the parts related to light source control in the electronic endoscope system 1 of Fig. 1 with reference to Fig. 2. Fig. 2 is a block diagram showing in more detail the parts related to light source control in the electronic endoscope system 1.

[0023] Referring to FIG. 2 , the light source module 30 includes an LED 31, a driver circuit 32, a memory 33, a photodetector 34, and an ADC (Analog to Digital Converter) 35. The control unit 21 includes a CPU 25 and a PWM adjustment unit 26. As described above, the light source module 30 includes one or more LEDs. However, since the configuration for processing each LED is the same, the following description will focus on one LED system. For example, FIG. 2 illustrates the light source module 30 with one driver circuit 32 and one LED 31 for the PWM waveform signal PWMOUT supplied from the control unit 21. If multiple LEDs are included, multiple systems corresponding to the number of LEDs actually installed are provided in the light source module 30. Note that the following description will be given using an example in which the LEDs are PWM dimmed, but analog dimming is equally applicable.

[0024] The memory 23 (an example of a second storage device) stores a correction coefficient for linearizing the output characteristics of the LED 31. Because the memory 23 is provided in the processor 20, it will be referred to as the "processor-side memory" hereinafter. When the processor 20 starts up, the CPU 25 generates and outputs a PWM waveform signal PWM for operating the LED 31 of the light source module 30. The duty ratio of the generated signal PWM is a value corresponding to the required illuminance based on an operation input to the operation panel 24 or an automatic dimming control (not shown). Note that the generation and output of the signal PWM may be performed by an ASIC, FPGA, or the like (not shown) instead of the CPU 25. The PWM adjustment unit 26 adjusts the duty ratio of the signal PWM supplied from the CPU 25 according to the correction coefficient stored in the memory 23 or memory 33, and generates a PWM waveform signal PWMOUT after adjusting (correcting) the duty ratio.

[0025] The driver circuit 32 drives the LED 31 based on the signal PWMOUT supplied from the control unit 21. The memory 33 (an example of a first storage device) stores a correction coefficient for linearizing the output characteristics of the LED 31. Because the memory 33 is provided in the light source module 30, it will be referred to as the "light source-side memory" below as appropriate. The data stored in the light source-side memory 33 is configured to be readable by the CPU 25. If there are no problems in the startup process described below, the same correction coefficients are stored in the light source-side memory 33 and the processor-side memory 23.

[0026] The photodetector 34 is formed of, for example, a photodiode (PD) and outputs an electrical signal (analog signal) corresponding to the light intensity of the light emitted from the LED 31. The ADC 35 converts the electrical signal output from the photodetector 34 into a digital signal and sends it to the CPU 25. As will be described later, the output signal from the photodetector 34 is used by the CPU 25 to determine which of the correction coefficients stored in the light source-side memory 33 and the processor-side memory 23 is more likely.

[0027] Next, the calibration performed during the manufacture of the light source module 30 will be described with reference to Figures 3 to 5. Figure 3 is a diagram showing the configuration when calibrating the LEDs 31. As described above, during the manufacture of the light source module 30, calibration is performed for each of one or more LEDs of the light source module 30.

[0028] When performing calibration, as shown in FIG. 3 , a light quantity meter 50 and a calibration device 60 are connected to the light source module 30 to be calibrated. The light quantity meter 50 acquires light emitted from the LED 31 and supplies an electrical signal (analog signal) corresponding to the light quantity (or illuminance) of the emitted light to the calibration device 60. The calibration device 60 includes a CPU 61 and an ADC 62. The CPU 61 is configured to execute a predetermined calibration program. By executing the calibration program, it generates a PWM waveform signal PWM with various duty ratios and supplies the signal to the driver circuit 32. The CPU 61 acquires the output of the photodetector 34 (corresponding to the illuminance of the LED 31) for various duty ratios of the signal PWM and calculates a correction coefficient (described later). The ADC 62 converts the electrical signal supplied from the light quantity meter 50 into a digital signal and sends it to the CPU 61. The electrical signal output from the photodetector 34 of the light source module 30 is also converted into a digital signal by the ADC 35 and sent to the CPU 61.

[0029] As an example, Figure 4 shows an example of the relationship between the duty ratio of the signal PWM and the illuminance (illuminance at a position a predetermined distance away from the LED) for an LED before correction. Before correction, the relationship between the duty ratio and the illuminance of the LED is nonlinear. In calibration, this relationship between the duty ratio of the signal PWM and the illuminance of the LED before correction is obtained, and the relationship between the duty ratio of the signal PWM and the duty ratio of the signal PWMOUT is determined so that the relationship between the duty ratio of the signal PWM and the illuminance of the LED becomes linear.

[0030] Here, when the duty ratio of the signal PWM is x and the duty ratio of the signal PWMOUT is y, the CPU 61 executes a predetermined calibration program to calculate the correction coefficients C0 to C6 of the polynomial model shown in the following equation (1) so that the relationship between the duty ratio of the signal PWMOUT and the illuminance of the LED becomes linear: y=C6·x ６ +C5・x ５ +C4 x ４ +C3 x ３ +C2 x ２+C1·x+C0 (1) Note that the above polynomial model is just an example, and any model can be applied. The calibration program calculates correction coefficients to ensure the linearity of the LED using the above polynomial model or another model.

[0031] The CPU 61 of the calibration device 60 calculates the correction coefficients C0 to C6 by executing the calibration program, and then writes the calculated correction coefficients to the light source-side memory 33 of the light source module 30, as shown in Fig. 5. The example shown in Fig. 5 shows a case where all of the correction coefficients recorded in the light source-side memory 33 before writing are "0", and the correction coefficients C6, C5, C4, C3, C2, C1, and C0 to be written are a, b, c, d, e, f, and g, respectively.

[0032] The CPU 61 also writes the output signal (digital value; referred to as the "PD output") of the photodetector 34 under predetermined conditions to the light-source-side memory 33. The PD output under these predetermined conditions is referred to as a "calibration representative value" (an example of a reference light intensity value). The "predetermined condition" is not limited, but the following description will be given assuming that the PD output is obtained when the duty ratio of the PWM signal supplied by the CPU 61 is 30%. The "predetermined condition" may be any duty ratio, as long as the condition does not change depending on the time when the PD output is acquired (e.g., during calibration, system startup, system operation, etc.). In other words, the "predetermined condition" when the PD output is acquired is always the same. The calibration representative value written to the light-source-side memory 33 is compared with the PD output obtained under the same conditions when the electronic endoscope system 1 is started and used for fault detection.

[0033] The light source module 30 for which the calibration has been completed is incorporated into the processor 20. When the electronic endoscope system 1 is first started up after the light source module 30 has been incorporated into the processor 20, the control unit 21 of the processor 20 writes the correction coefficients and calibration representative values ​​recorded in the light source-side memory 33 into the processor-side memory 23.

[0034] 6 shows examples of correction coefficients and calibration representative values ​​recorded in the processor-side memory 23 and the light source-side memory 33 before and after the light source module 30 is incorporated into the processor 20. Before the incorporation, the values ​​recorded in the light source-side memory 33 are the values ​​after the calibration shown in FIG. 5 is executed. Before the incorporation, the processor-side memory 23 stores the initial values ​​(here, all "0") at the time of shipment from the factory. When the light source module 30 is incorporated into the processor 20, the processor-side memory 23 and the light source-side memory 33 store the same correction coefficients and the same calibration representative values, as shown in FIG.

[0035] After writing the data, it is preferable to read the data recorded in the processor-side memory 23 and verify the read data. For example, if the value read from the processor-side memory 23 does not match the value read from the light source-side memory 33, the verification is deemed to be unsuccessful, and the processor-side memory 23 is determined to be faulty.

[0036] Next, the startup process of the electronic endoscope system 1 will be described with reference to the flowcharts of Figures 7 and 8. Note that the startup process shown in Figures 7 and 8 refers to each subsequent startup process, assuming that the same correction coefficients and the same calibration representative values ​​are stored in the processor-side memory 23 and the light-source-side memory 33 upon initial startup of the electronic endoscope system 1. The startup process shown in Figures 7 and 8 is executed by the processor 20 (mainly the control unit 21 of the processor 20).

[0037] In the startup process, the processor 20 first sequentially reads the correction coefficients and calibration representative values ​​stored in the processor-side memory 23 and the light-source-side memory 33 (steps S2 and S4). The calibration representative values ​​read from the processor-side memory 23 and the light-source-side memory 33 are examples of the second light intensity value and the first light intensity value, respectively. Next, the processor 20 acquires the representative output value (PD output) of the PD of the photodetector 34 (referred to as "PD" in the flowchart; an example of a startup light intensity value) when the control unit 21 outputs a PWM signal with a duty cycle of 30% (the same conditions as when the calibration representative value is acquired) (step S6). Note that when acquiring the PD output, the PWM adjustment unit 26 ( FIG. 2 ) does not adjust the duty cycle. In other words, the PWM signal generated by the control unit 21 is supplied to the light source module 30 as is. This ensures that the PD output is obtained under the same conditions as when the calibration representative value was acquired during calibration.

[0038] The control unit 21 compares the PD output acquired in step S6 with the calibration representative value V ＬＳ The processor compares the PD output and the processor-side memory 23 and determines whether the difference between them is less than a predetermined threshold value TH (step S8). If the difference between them is less than the threshold value TH (step S8: YES), the PD output is approximately the same as the calibration representative value obtained when the light source module 30 was calibrated, and the reliability of the data in the light-source-side memory 33 is considered to be high. In this case, the processor further reads out the correction coefficients C0 to C6 from the light-source-side memory 33 and the processor-side memory 23 and determines whether the correction coefficients C0 to C6 all match. If they match (step S16: YES), both the light-source-side memory 33 and the processor-side memory 23 are considered to be normal, and the startup process is terminated.

[0039] Conversely, if at least one of the correction coefficients C0 to C6 does not match between the light source-side memory 33 and the processor-side memory 23 (step S16: NO), this means that the data in the processor-side memory 23 indicates a value different from the data in the light source-side memory 33 that was deemed to be highly reliable in step S8. In this case, the control unit 21 determines that the data stored in the light source-side memory 33 is more likely than the data stored in the processor-side memory 23. Furthermore, the control unit 21 overwrites the correction coefficients C0 to C6 in the light source-side memory 33 to the processor-side memory 23 (step S18).

[0040] 9 shows an example of a case where data does not match between the light source-side memory 33 and the processor-side memory 23. In this example, the data in the light source-side memory 33 has changed from the state at the time of initial system startup (the state after installation in FIG. 6) to ax, bx, cx, dx, ex, fx, and gx, resulting in a data mismatch between the memories. In this case, data overwriting in step S18 changes the data in the processor-side memory 23 to ax, bx, cx, dx, ex, fx, and gx, thereby making the data match between the memories.

[0041] If it is confirmed as a result of the overwriting in step S18 that the values ​​of the correction coefficients C0 to C6 in the processor-side memory 23 and the light-source-side memory 33 all match (step S20: YES), the startup process is terminated because the data in the processor-side memory 23 has been restored. If the values ​​of the correction coefficients C0 to C6 in the processor-side memory 23 and the light-source-side memory 33 do not all match even after the overwriting in step S18 (step S20: NO), the control unit 21 determines that the processor-side memory 23 has failed or deteriorated (step S22), outputs a warning to the monitor 40 or the like (step S24), and then terminates the startup process.

[0042] The control unit 21 compares the PD output acquired in step S6 with the calibration representative value V ＬＳIf the difference between the two is equal to or greater than a predetermined threshold value TH (step S8: NO), it can be determined that the light source side memory 33 may be broken or deteriorated. In this case, the process proceeds to step S10, and the PD output acquired in step S6 and the calibration representative value V read from the processor side memory 23 are compared. ＰＲ and determine whether the difference between them is less than a predetermined threshold value TH.

[0043] If the difference between the two is equal to or greater than the threshold value TH in step S10 (step S10: NO), the calibration representative value V ＰＲ , the calibration representative value V read out from the light source side memory 33 ＬＳ , and the PD output, only the PD output deviates from the other two calibration representative values, which indicates a high possibility of failure or degradation of the light source module 30. Therefore, the control unit 21 determines that the light source module 30 has failed or deteriorated (step S12), outputs a warning to the monitor 40 or the like (step S14), and then terminates the startup process. Note that possible failures or deterioration of the light source module 30 include failure of the transistor element of the driver circuit 32, failure or deterioration of the LED 31, failure or deterioration of the photodetector 34, failure of the ADC 35, misalignment of the optical path axis of the light emitted from the LED 31, deterioration of the optical path due to ultraviolet rays, etc.

[0044] If the difference between the two is less than the threshold value TH in step S10 (step S10: YES), the PD output is approximately the same as the calibration representative value written at the first startup after the light source module 30 is incorporated into the processor 20, and therefore the reliability of the data in the processor-side memory 23 is considered to be high. ＰＲ , the calibration representative value V read out from the light source side memory 33 ＬＳ , and the representative value V for calibration of the PD output in the light source side memory 33 ＬＳSince only the value C0 deviates from the other two values, there is a high possibility of failure or deterioration of the light source module 30. In this case, the control unit 21 determines that the data stored in the processor-side memory 23 is more likely to be accurate than the data stored in the light source-side memory 33. Furthermore, the control unit 21 overwrites the light source-side memory 33 with the correction coefficients C0 to C6 from the processor-side memory 23 (step S26).

[0045] 10 shows an example of a case where data between memories does not match due to data loss in light source-side memory 33. In this example, data has been lost in light source-side memory 33 from the state at the time of initial system startup (the state after installation in FIG. 6), and correction coefficients C0 to C6 are all set to 0. In this case, data overwriting in step S26 results in the data in light source-side memory 33 becoming a, b, c, d, e, f, and g, making the data match between memories.

[0046] If it is confirmed as a result of the overwriting in step S26 that the values ​​of the correction coefficients C0 to C6 in the processor-side memory 23 and the light source-side memory 33 all match (step S28: YES), the startup process is terminated since the data in the light source-side memory 33 has been restored.

[0047] If the values ​​of the correction coefficients C0 to C6 in the processor-side memory 23 and the light source-side memory 33 do not all match even after the overwrite in step S26 (step S28: NO), the control unit 21 determines that the light source-side memory 33 has failed or deteriorated (step S30), outputs a warning to the monitor 40, etc. (step S32), and then terminates the startup process.

[0048] As described above, in the electronic endoscope system 1 of the embodiment, the control unit 21 of the processor 20 writes the correction coefficients and calibration representative values ​​read from the light source memory 33 of the light source module 30 to the processor memory 23 after the light source module 30 is incorporated into the processor 20. Furthermore, at system startup, as shown in Figures 7 and 8, the control unit 21 compares the PD output of the LED 31 obtained under predetermined conditions with the calibration representative values ​​read from the light source memory 33 and the processor memory 23, and determines which of the data stored in the light source memory 33 and the processor memory 23 is more likely based on the comparison results. This provides the following advantages.

[0049] When data for correcting the LED output characteristics is stored in memory, the processor-side memory and the light-source-side memory are configured redundantly. The PD output of the photodetector sequentially acquired by the processor is compared with data read from the processor-side memory and data read from the light-source-side memory for mutual monitoring. This ensures data robustness without the need for high-durability memory. By using a photodetector that detects the light emitted from the LED installed in the processor, it is easy to identify whether the processor-side memory, the light-source-side memory, or a component other than the light-source-side memory in the light source module is faulty or degraded. As described above, calibration is performed using a light intensity meter and a calibration device during the manufacture of the light source module, and correction coefficients, etc. are written to the light-source-side memory. However, these written correction coefficients, etc. are copied and written to the processor-side memory when the light source module is incorporated into the processor. Therefore, recalibration is not required when the light source module is incorporated into the processor, thereby streamlining the manufacturing process.

[0050] The electronic endoscope system of the present invention has been described in detail above, but the electronic endoscope system of the present invention is not limited to the above-described embodiment, and various improvements and modifications may be made without departing from the spirit and scope of the present invention.

[0051] The present invention is related to patent application No. 2023-210077, filed with the Japan Patent Office on December 13, 2023, the entire contents of which are incorporated herein by reference.

Claims

1. An electronic endoscope system configured to capture images of biological tissue, comprising: a processor for processing captured images of the biological tissue; and a light source module that can be incorporated into the electronic endoscope processor and generates illumination light for the biological tissue based on light emitted from at least one light-emitting element, the light source module comprising: a first storage device that stores a correction coefficient for correcting output characteristics of the light-emitting element and a reference light amount value of the light-emitting element under specified conditions, the correction coefficient being obtained before the light source module is incorporated into the processor; the processor comprising: a second storage device, a photodetector that detects the light amount of the light-emitting element, and a control unit, the control unit writing the correction coefficient and the reference light amount value read from the first storage device into the second storage device after the light source module is incorporated into the processor, an electronic endoscope system which, upon system startup, compares a startup light intensity value which is a reference light intensity value of the light-emitting element obtained under the specified conditions with a first light intensity value which is a reference light intensity value read from the first storage device and a second light intensity value which is a reference light intensity value read from the second storage device, and determines which of the data stored in the first storage device and the data stored in the second storage device is more likely based on the comparison results.

2. The electronic endoscope system of claim 1, wherein the control unit determines that the light source module is malfunctioning when the difference between the startup light intensity value and the first light intensity value is greater than a predetermined threshold value and when the difference between the startup light intensity value and the second light intensity value is greater than a predetermined threshold value.

3. The electronic endoscope system of claim 1, wherein the control unit determines that the data stored in the second storage device is more likely to be reliable than the data stored in the first storage device when the difference between the startup light intensity value and the first light intensity value is greater than a predetermined threshold and the difference between the startup light intensity value and the second light intensity value is less than a predetermined threshold.

4. The electronic endoscope system according to claim 3, wherein the control unit overwrites the first storage device with the data read from the second storage device when the control unit determines that the data stored in the second storage device is more likely to be accurate.

5. The electronic endoscope system of claim 1, wherein the control unit determines that the data stored in the first memory device is more likely to be reliable than the data stored in the second memory device when the difference between the startup light intensity value and the first light intensity value is less than a predetermined threshold value and the difference between the startup light intensity value and the second light intensity value is greater than a predetermined threshold value.

6. The electronic endoscope system according to claim 5, wherein the control unit overwrites the data read from the first storage device to the second storage device when the control unit determines that the data stored in the first storage device is more likely to be accurate.

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