Electronic endoscope system

Abstract

To provide an electronic endoscope system capable of securing robust property of data, without using a high durable storage unit in the system.SOLUTION: An electronic endoscope system in one embodiment has: a processor; and a light source module including a light emission element. The light source module has a first storage unit which stores a reference light quantity value of the light emission element in a prescribed condition. The processor has a second storage unit and a control part. The control part writes the reference light quantity value read from the first storage unit, to the second storage unit, after incorporating the light source module, compares a start-time light quantity value which is the reference light quantity value of the light emission element acquired in the prescribed condition in start-up of the system, with each of a first light quantity value being the reference light quantity value read from the first storage unit, and a second light quantity value being the reference light quantity value read from the second storage unit, and on the basis of the comparison result, determines whether the data in the first storage unit or the data in the second storage unit is probable data.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to an electronic endoscope system configured to image a living tissue.

Background Art

[0002] In the field of medical devices, an endoscope system capable of generating a suitable image for diagnosing a lesion hidden in a body cavity by illuminating a living tissue in the body cavity and imaging the illuminated living tissue in the body cavity as a subject is known. Conventionally, a lamp light source such as a xenon lamp or a halogen lamp that emits white light as illumination light has been used. Recently, however, a light source module including a light emitting diode (LED) that emits light in a specific wavelength band has been used instead of the lamp light source (for example, Patent Document 1).

[0003] Since the output characteristics of the emitted light of the light source are generally non-linear, the output characteristics of the light source are measured in advance by a calibration device, and a correction coefficient for linearly correcting the output characteristics is recorded in a non-volatile memory. When using the light source module, the output characteristics of the emitted light are linearly corrected using the recorded correction coefficient.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] Employing a highly durable storage device (memory) as a non-volatile memory for storing correction factors for correcting the output characteristics of a light source leads to an increase in the cost of the system, which is not preferable. On the other hand, if the data recorded in the storage device is lost without employing a highly durable storage device, it is necessary to measure the output characteristics of the light source again using calibration equipment to determine the correction factor. However, since the measurement requires a lot of man-hours, the re-calibration work is complicated. Even when replacing the light source module itself, a calibration operation for the new light source module is required, which is also complicated.

[0006] Therefore, an object of the present invention is to ensure the robustness of data without using a highly durable storage device when storing data for correcting the output characteristics of a light source in an electronic endoscope system.

Means for Solving the Problems

[0007] One aspect of the present disclosure is an electronic endoscope system configured to image a living tissue, a processor that processes an image of the living tissue, and a light source module that can be incorporated into the processor for the electronic endoscope and generates illumination light for the living 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 factor for correcting the output characteristics of the light-emitting element and a reference light amount value of the light-emitting element under predetermined conditions, which are obtained before the light source module is incorporated into the processor. The processor includes a second storage device, a photodetector that detects the light amount 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 factor and the reference light amount value read from the first storage device to the second storage device. When the system is started up, the light quantity value at startup, which is the reference light quantity value of the light-emitting element acquired under the predetermined conditions, is compared with each of the first light quantity value, which is the reference light quantity value read from the first storage device, and the second light quantity value, which is the reference light quantity value read from the second storage device. Based on the comparison result, it is determined which of the data stored in the first storage device and the second storage device is more reliable data.

[0008] When the difference between the light quantity value at startup and the first light quantity value is greater than a predetermined threshold value, and the difference between the light quantity value at startup and the second light quantity value is greater than a predetermined threshold value, the control unit may determine that there is a failure in the light source module.

[0009] When the difference between the light quantity value at startup and the first light quantity value is greater than a predetermined threshold value, and the difference between the light quantity value at startup and the second light quantity value is less than a predetermined threshold value, the control unit may determine that the data stored in the second storage device is more reliable than the data stored in the first storage device.

[0010] When the control unit determines that the data stored in the second storage device is more reliable, the data read from the second storage device may be overwritten on the first storage device.

[0011] When the difference between the light quantity value at startup and the first light quantity value is less than a predetermined threshold value, and the difference between the light quantity value at startup and the second light quantity value is greater than a predetermined threshold value, the control unit may determine that the data stored in the first storage device is more reliable than the data stored in the second storage device.

[0012] When the control unit determines that the data stored in the first storage device is more reliable, the data read from the first storage device may be overwritten on the second storage device.

Advantages of the Invention

[0013] According to the above-described electronic endoscope system, in the case of storing data for correcting the output characteristics of the light source in the storage device in the electronic endoscope system, the robustness of the data can be ensured without using a highly durable storage device.

Brief Description of the Drawings

[0014]

Figure 1

Figure 2

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Embodiments for Carrying Out the Invention

[0015] Hereinafter, the electronic endoscope system of the present embodiment will be described in detail with reference to the drawings. FIG. 1 is a block diagram showing an example of the configuration of the electronic endoscope system 1 according to the present embodiment. As shown in FIG. 1, the electronic endoscope system 1 is a system specialized for medical use, and includes an electronic endoscope (endoscope) 10, an electronic endoscope processor 20 (hereinafter simply referred to as "processor 20") to which the electronic scope 10 is connected by a connector, and a monitor 40.

[0016] The processor 20 includes a control unit 21. The control unit 21 has a CPU that executes various programs stored in the memory 23, and integrally controls the entire electronic endoscope system 1. Further, the control unit 21 is connected to an operation panel 24. The control unit 21 changes each operation of the electronic endoscope system 1 and parameters for each operation according to an instruction from an operator input to the operation panel 24. The control unit 21 supplies a clock pulse serving as a reference for the timing of operations of each unit in the electronic endoscope system 1 to each unit in the system.

[0017] The processor 20 is provided with a light source module 30. The light source module 30 has a light emitting element (LED: Light Emitting Device) that emits illumination light for illuminating a subject such as a living tissue in a body cavity. When one LED is used, the LED is preferably a white LED. Although not shown, a plurality of LEDs may be provided. The plurality of LEDs each have a different wavelength band of emitted light. In one example, they 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 synthesizing the emitted lights of the plurality of LEDs. White light is light having a flat spectral intensity distribution in the visible light band, and pseudo-white light is light in which the spectral intensity distribution is not flat and lights in a plurality of wavelength bands are mixed. The illumination light of the light source module 30 is condensed on the incident end face of the LCB (Light Carrying Bundle) 11 provided in the electronic scope 10 and enters the LCB 11. Further, the illumination light emitted from the exit end face of the LCB 11 is irradiated onto the subject through the light distribution lens 12. The 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 the image sensor 14 through the objective lens 13.

[0018] When manufacturing the light source module 30, as will be described later, calibration is performed for each of one or more LEDs of the light source module 30. Calibration is a process for ensuring the linearity of the LEDs. As dimming methods for the LEDs, PWM dimming and analog dimming are known. PWM dimming is a method of adjusting the illuminance of the LED by adjusting the duty ratio of the PWM signal, and analog dimming is a method of adjusting the illuminance of the LED by changing the amount of current supplied to the LED. In the case of either dimming method, for the LEDs before calibration, since the relationship between the duty ratio of the PWM signal or the input such as current and the illuminance of the LED is not linear, the purpose of calibration is to set a correction coefficient for adjusting this relationship to be linear.

[0019] The light source module 30 is configured to be incorporable into the housing (not shown) of the processor 20. During the manufacture of the light source module 30, calibration is performed for each of one or more LEDs, and then the calibrated light source module 30 is incorporated into the processor 20. Also, when the light source module 30 fails or deteriorates over time, a new light source module 30 can be incorporated into the processor 20 after calibration.

[0020] The image sensor 14 is an image sensor having a Bayer-type pixel arrangement. The image sensor 14 accumulates the optical image formed at each pixel on the light-receiving surface as electric charges according to the amount of light, reads them out, generates imaging data, and outputs it. Note that as the image sensor 14, a CMOS image sensor, a CCD image sensor, or other types of imaging devices can be adopted. The image sensor 14 may also be equipped with a complementary color filter.

[0021] The electronic endoscope 10 includes a signal processing unit 15 in the connection part with the processor 20. Under the control of the control unit 21, the signal processing unit 15 performs a process of driving the image sensor 14 and acquires imaging data from the image sensor 14. In one embodiment, the signal processing unit 15 supplies a synchronization signal (for example, a vertical synchronization signal) of one frame to the image sensor 14, acquires imaging data of the subject from the image sensor 14 in units of frames, and transmits it to the image processing unit 22 of the processor 20. The frame period is, for example, 1 / 30 second or 1 / 60 second. Note that it is not limited to the case where the signal processing unit 15 supplies a synchronization signal of one frame. Depending on the image sensor, imaging data may be transmitted based on a synchronization signal created by itself. In that case, it is not necessary for the signal processing unit 15 to supply a synchronization signal of one frame to the image sensor.

[0022] After buffering the imaging data output from the signal processing unit 15 and performing predetermined image processing on the imaging data, the image processing unit 22 of the processor 20 generates a video format signal and outputs it to the monitor 40. Examples of image processing include demosaicing processing, matrix operation, edge enhancement processing, and the like.

[0023] Next, with reference to FIG. 2, the part related to the light source control in the electronic endoscope system 1 of FIG. 1 will be described. FIG. 2 is a block diagram showing in more detail the part related to the light source control of the electronic endoscope system 1.

[0024] 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 (Analogue to Digital Converter) 35. The control unit 21 has a CPU 25 and a PWM adjustment unit 26. As described above, the light source module 30 includes one or more LEDs. Since the configuration for processing each LED is the same, hereinafter, one set of LEDs will be described. For example, in FIG. 2, the light source module 30 shows one set of driver circuit 32 and LED 31 with respect to the PWM waveform signal PWMOUT supplied from the control unit 21. When a plurality of LEDs are provided, a plurality of sets corresponding to the actual number of LEDs provided are provided in the light source module 30. Hereinafter, an example in the case where the LED is PWM dimming will be described, but the case of analog dimming can be applied in the same manner.

[0025] The memory 23 (an example of the second storage device) stores a correction coefficient for linearizing the output characteristics of the LED 31. Since the memory 23 is provided in the processor 20, hereinafter, it will be appropriately referred to as the "processor-side memory". When the processor 20 is activated, 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 the operation input to the operation panel 24 or the automatic dimming control (not shown). Note that the generation and output of the signal PWM may be configured to be executed by an ASIC, FPGA, etc. (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 the memory 33, and generates a PWM waveform signal PWMOUT with the duty ratio adjusted (corrected).

[0026] 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 the first storage device) stores a correction coefficient for linearizing the output characteristics of the LED 31. Since the memory 33 is provided in the light source module 30, it will be hereinafter referred to as the "light source side memory" as appropriate. The data stored in the light source side memory 33 is configured to be readable by the CPU 25. If there is no problem in the startup process described later, the same correction coefficient is stored in the light source side memory 33 and the processor side memory 23.

[0027] The photodetector 34 is composed of, for example, a photodiode (PD), and outputs an electrical signal (analog signal) corresponding to the light intensity of the emitted light of 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 of the photodetector 34 is used for the CPU 25 to determine which of the correction coefficient stored in the light source side memory 33 and the correction coefficient stored in the processor side memory 23 is more reliable.

[0028] Next, the calibration performed during the manufacture of the light source module 30 will be described with reference to FIGS. 3 to 5. FIG. 3 is a diagram showing the configuration when calibrating the LED 31. As described above, when manufacturing the light source module 30, calibration is performed for each of one or more LEDs of the light source module 30.

[0029] When performing calibration, as shown in FIG. 3, a light quantity measuring device 50 and a calibration device 60 are connected to the light source module 30 to be calibrated. The light quantity measuring device 50 acquires the emitted light of 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, a signal PWM of a PWM waveform with various duty ratios is generated and supplied 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 measuring device 50 into a digital signal and sends it to the CPU 61. Also, the electrical signal output from the photodetector 34 of the light source module 30 is converted into a digital signal by the ADC 35 and sent to the CPU 61.

[0030] As an example, FIG. 4 shows an example of the relationship between the duty ratio of the signal PWM and the illuminance (the illuminance at a position separated from the LED by a predetermined distance) for the LED before correction. Before correction, the relationship between the duty ratio and the illuminance of the LED is non-linear. In calibration, the relationship between the duty ratio of the signal PWM before correction and the illuminance of the LED is acquired, 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 PWMOUT and the illuminance of the LED becomes linear.

[0031] Here, when the duty ratio of the signal PWM is x and the duty ratio of the signal PWMOUT is y, the CPU 61 calculates the correction coefficients C0 to C6 of the polynomial model shown in the following formula (1) so that the relationship between the duty ratio of the signal PWMOUT and the illuminance of the LED becomes linear by executing a predetermined calibration program. 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 an example, and any model can be applied. The calibration program calculates a correction coefficient for ensuring the linearity of the LED using the above polynomial model or another model.

[0032] When the CPU 61 of the calibration device 60 calculates the correction coefficients C0 to C6 by executing a calibration program, as shown in FIG. 5, the calculated correction coefficients are written into the light source side memory 33 of the light source module 30. In the example shown in FIG. 5, the case where all 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, C0 to be written are a, b, c, d, e, f, g respectively is shown as an example.

[0033] Also, the CPU 61 writes the output signal (digital value; referred to as "PD output") of the photodetector 34 under a predetermined condition into the light source side memory 33. This PD output under the predetermined condition is referred to as the "representative value for calibration" (an example of the reference light quantity value). Although the "predetermined condition" is not limited, hereinafter, the case where the PD output is the one when the duty ratio of the signal PWM supplied by the CPU 61 is 30% will be described. The "predetermined condition" may be any duty ratio condition as long as the condition is not changed according to the time point when the PD output is acquired (for example, during calibration execution, system startup, system operation, etc.). In other words, the "predetermined condition" for acquiring the PD output is always the same condition. Here, the representative value for calibration written into 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 is used for failure determination.

[0034] The light source module 30 for which calibration has been completed is incorporated into the processor 20. At the first startup of the electronic endoscope system 1 after the light source module 30 is incorporated into the processor 20, the control unit 21 of the processor 20 writes the correction coefficients and the representative value for calibration recorded in the light source side memory 33 into the processor side memory 23.

[0035] FIG. 6 shows examples of the correction coefficients and the representative value for calibration 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 incorporation, the values recorded in the light source side memory 33 are the values after the calibration shown in FIG. 5. Before incorporation, the initial values at the time of factory shipment (here, all are "0") are recorded in the processor side memory 23. When the light source module 30 is incorporated into the processor 20, as shown in FIG. 6, the same correction coefficient and the same representative value for calibration are recorded in the processor side memory 23 and the light source side memory 33.

[0036] Note that it is preferable to read out the data recorded in the processor side memory 23 after writing the data 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, it is determined that the verification has failed and that there is a failure in the processor side memory 23.

[0037] Next, with reference to the flowcharts of FIGS. 7 and 8, the startup process of the electronic endoscope system 1 will be described. Note that the startup process shown in FIGS. 7 and 8 is based on the premise that the same correction coefficient and the same representative value for calibration are recorded in the processor side memory 23 and the light source side memory 33 by the first startup of the electronic endoscope system 1, and means every subsequent startup process. The startup process shown in FIGS. 7 and 8 is executed by the processor 20 (mainly the control unit 21 of the processor 20).

[0038] In the startup process, first, the processor 20 sequentially reads out the correction coefficient and the representative value for calibration recorded in the processor side memory 23 and the light source side memory 33 (steps S2, S4). Here, the representative values for calibration read from the processor side memory 23 and the light source side memory 33 are examples of the second light quantity value and the first light quantity value, respectively. Next, the processor 20 acquires the representative output value (PD output) of the PD of the photodetector 34 when the signal PWM with a duty ratio of 30% (the same condition as when acquiring the representative value for calibration) is output from the control unit 21 (step S6). (In the flowchart, it is denoted as "PD"; an example of the light quantity value at startup). When obtaining the PD output, the duty ratio adjustment by the PWM adjustment unit 26 (Fig. 2) is not performed. That is, the signal PWM generated by the control unit 21 is directly supplied to the light source module 30. As a result, the PD output is obtained under the same conditions as when the calibration representative value was obtained during the execution of calibration.

[0039] The control unit 21 compares the PD output obtained in step S6 with the calibration representative value V read from the light source side memory 33 LS and determines whether the difference between the two is less than a predetermined threshold TH (step S8). If the difference between the two is less than the threshold TH (step S8: YES), since the PD output is almost the same as the calibration representative value obtained when calibration was performed on the light source module 30, the reliability of the data in the light source side memory 33 is considered to be high. In that case, further, correction coefficients C0 to C6 are read from the light source side memory 33 and the processor side memory 23, and it is determined whether all of the correction coefficients C0 to C6 match. If they match (step S16: YES), since it is considered that both the light source side memory 33 and the processor side memory 23 are normal, the startup process is terminated.

[0040] 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), it means that the data in the processor side memory 23 shows a value different from the data in the light source side memory 33, which was considered to be highly reliable in step S8. In that case, the control unit 21 determines that the data stored in the light source side memory 33 is more reliable than the data stored in the processor side memory 23. Further, 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).

[0041] Fig. 9 shows an example where data is inconsistent 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 to ax, bx, cx, dx, ex, fx, gx from the state at the first system startup (the state after incorporation in Fig. 6), resulting in inconsistent data between the memories. In this case, the data overwrite in step S18 makes the data in the processor side memory 23 become ax, bx, cx, dx, ex, fx, gx, making the data consistent between the memories.

[0042] If it can be confirmed that all the values of the correction coefficients C0 to C6 of the processor side memory 23 and the light source side memory 33 are the same as a result of the overwrite in step S18 (step S20: YES), since the data in the processor side memory 23 has been restored, the startup process ends. If all the values of the correction coefficients C0 to C6 of the processor side memory 23 and the light source side memory 33 are not the same even after the overwrite in step S18 (step S20: NO), the control unit 21 determines that there is a failure or degradation in the processor side memory 23 (step S22), outputs a warning to the monitor 40 or the like after that (step S24), and then ends the startup process.

[0043] The control unit 21 compares the PD output acquired in step S6 with the calibration representative value V read from the light source side memory 33 LS As a result of the comparison, if the difference between the two is equal to or greater than a predetermined threshold TH (step S8: NO), it can be determined that there may be a failure or degradation in the light source side memory 33. In that case, the process proceeds to step S10, and the PD output acquired in step S6 is compared with the calibration representative value V read from the processor side memory 23 PR to determine whether the difference between the two is less than the predetermined threshold TH.

[0044] If the difference between the two is equal to or greater than the threshold TH in step S10 (step S10: NO), the calibration representative value V read from the processor side memory 23 PR and the calibration representative value V read from the light source side memory 33 LSAmong the PD output, only the PD output deviates from the other two representative values for calibration, so there is a high possibility of a failure or deterioration of the light source module 30. Therefore, the control unit 21 determines that there is a failure or deterioration of the light source module 30 (step S12), outputs a warning to the monitor 40 or the like (step S14), and then ends the startup process. Regarding the failure or deterioration of the light source module 30, a failure of a transistor element in the driver circuit 32, a failure or deterioration of the LED 31, a failure or deterioration of the photodetector 34, a failure of the ADC 35, a deviation of the optical axis of the emitted light of the LED 31, deterioration due to ultraviolet rays in the optical path, etc. can be considered.

[0045] If the difference between the two is less than the threshold TH in step S10 (step S10: YES), since the PD output is almost the same as the representative value for calibration written at the first startup after the light source module 30 is incorporated into the processor 20, it is considered that the reliability of the data in the processor-side memory 23 is high. That is, the representative value for calibration V read from the processor-side memory 23 PR and the representative value for calibration V read from the light source-side memory 33 LS Among the PD output, only the representative value for calibration V of the light source-side memory 33 LS deviates from the other two values, so there is a high possibility of a 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 reliable than the data stored in the light source-side memory 33. Further, the control unit 21 overwrites the correction coefficients C0 to C6 of the processor-side memory 23 to the light source-side memory 33 (step S26).

[0046] FIG. 10 shows an example in the case where the data between the memories is inconsistent due to the disappearance of the data in the light source-side memory 33. In this example, the data in the light source-side memory 33 disappears from the state at the first system startup (the state after incorporation in FIG. 6), and all the correction coefficients C0 to C6 are 0. In this case, by overwriting the data in step S26, the data in the light source-side memory 33 becomes a, b, c, d, e, f, g, and the data between the memories is made consistent.

[0047] As a result of the overwrite in step S26, if it can be confirmed 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), since the data in the light source-side memory 33 has been restored, the startup process is terminated.

[0048] If, even after the overwrite in step S26, 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 (step S28: NO), the control unit 21 determines that there is a failure or deterioration in the light source-side memory 33 (step S30), outputs a warning to the monitor 40 or the like (step S32), and then terminates the startup process.

[0049] As described above, in the electronic endoscope system 1 according to the embodiment, after the light source module 30 is incorporated into the processor 20, the control unit 21 of the processor 20 writes the correction coefficients and the representative values for calibration read from the light source-side memory 33 of the light source module 30 into the processor-side memory 23. Furthermore, as shown in FIGS. 7 and 8, at the time of system startup, the control unit 21 compares the PD output of the LED 31 acquired under predetermined conditions with each of the representative values for calibration read from the light source-side memory 33 and the representative values for calibration read from the processor-side memory 23, and based on the comparison results, determines which of the data stored in the light source-side memory 33 and the processor-side memory 23 is more reliable data. Therefore, the following effects are exhibited.

[0050] When storing data for correcting the output characteristics of the LED in the memory, a redundant configuration of the processor-side memory and the light source-side memory is adopted, and the PD output of the photodetector sequentially acquired from the processor is compared with the data read from the processor-side memory and the data read from the light source-side memory for mutual monitoring. Therefore, the robustness of the data can be ensured without using a highly durable memory. By using a photodetector that detects the emitted light of an LED provided in the processor, it becomes easy to identify which of the components other than the processor-side memory, the light source-side memory, and the components in the light source module other than the light source-side memory are faulty or degraded. As described above, during the manufacture of the light source module, calibration is performed using a light quantity measuring device and a calibration device, and correction coefficients and the like are written into the light source-side memory. When the light source module is incorporated into the processor, these written correction coefficients and the like are copied and written into the processor-side memory. Therefore, since calibration is not required again when the light source module is incorporated into the processor, the manufacturing process can be rationalized.

[0051] As described above, the electronic endoscope system of the present invention has been described in detail. However, the electronic endoscope system of the present invention is not limited to the above-described embodiments, and various improvements and modifications may of course be made without departing from the gist of the present invention.

Explanation of Reference Numerals

[0052] 1... Electronic endoscope system 10... Electronic endoscope 11... LCB 12... Light distribution lens 13... Objective lens 14... Image sensor 15... Signal processing unit 20... Processor 21... Control unit 22... Image processing unit 23... Memory 24... Operation panel 25... CPU 26... PWM adjustment unit 30... Light source module 31... LED 32... Driver circuit 33... Memory 34... Photodetector 35... ADC 40... Monitor 50... Light quantity measuring device 60... Calibration device 61…CPU 62…ADC

Claims

1. An electronic endoscope system configured to image a biological tissue, a processor that processes an image of the biological tissue, a light source module that can be incorporated into the processor for the electronic endoscope and generates illumination light for the biological tissue based on light emitted from at least one light emitting element, the light source module, a first storage device that stores a correction coefficient for correcting the output characteristics of the light emitting element obtained before incorporating the light source module into the processor and a reference light amount value of the light emitting element under a predetermined condition, the processor, a second storage device, a photodetector that detects the light amount of the light emitting element, and a control unit, the control unit, after the light source module is incorporated into the processor, writes the correction coefficient and the reference light amount value read from the first storage device to the second storage device, at the time of system startup, compares the startup light amount value, which is the reference light amount value of the light emitting element acquired under the predetermined condition, with each of the first light amount value, which is the reference light amount value read from the first storage device, and the second light amount value, which is the reference light amount value read from the second storage device, and based on the comparison result, determines which of the data stored in the first storage device and the second storage device is more reliable data, An electronic endoscope system.

2. When the difference between the startup light amount value and the first light amount value is greater than a predetermined threshold and the difference between the startup light amount value and the second light amount value is greater than a predetermined threshold, the control unit determines that there is a failure in the light source module. The electronic endoscope system according to claim 1.

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

4. When the control unit determines that the data stored in the second storage device is more reliable, the control unit overwrites the data read from the second storage device to the first storage device. The electronic endoscope system according to claim 3.

5. When the difference between the startup light quantity value and the first light quantity value is less than a predetermined threshold and the difference between the startup light quantity value and the second light quantity value is greater than the predetermined threshold, the control unit determines that the data stored in the first storage device is more reliable than the data stored in the second storage device. The electronic endoscope system according to claim 1. **Claim 6** When the control unit determines that the data stored in the first storage device is more reliable, the control unit overwrites the data read from the first storage device to the second storage device. The electronic endoscope system according to claim 5.

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