Method for automatic calibration and automatic compensation of light output power of endoscope cold light source

Abstract

The present invention relates to a method for automatically calibrating the light output power and automatically compensating the light output power of an endoscope cold light source, belonging to the technical field of medical cold light sources. The automatic calibration before leaving the factory includes the following steps: (1) determining the target approximate relationship formula between the light power value and the driving current. (2) determining the list of segmented driving current values and saving them to the cold light source. (3) obtaining the target light power value and the light power measurement value. (4) performing automatic calibration. (5) calibrating the approximate relationship formula between the target feedback value and the driving current. The automatic compensation during use includes the following steps: (1) reading the target feedback value and the measured feedback value to determine the feedback attenuation coefficient. (2) performing automatic compensation. (3) recalculating the driving current values of each gear after compensation and saving them to a new list. (4) giving a prompt when the compensation upper limit is reached. The invention can reduce the difference in the light output power of different cold light sources and improve the light output stability.

Description

Technical Field

[0001] The present invention relates to the technical field of medical cold light sources, and particularly to a method for automatically calibrating and compensating the light output power of an endoscope cold light source. Background Art

[0002] With the development of semiconductor technology, more and more medical devices use LEDs or lasers as lighting sources. Due to the manufacturing processes of LED chips or laser chips, there are generally individual differences among them. For LEDs or lasers with the same wavelength, even when driven with the same magnitude of current, the light output powers are quite different. Therefore, only ensuring the consistency of the driving current of the cold light source cannot guarantee the consistency of the final light output intensity. In the prior art, to reduce such individual differences, the quality of LED chips or laser chips is strictly controlled, and qualified products are screened, but this method increases costs and makes the process more cumbersome.

[0003] In addition, long-term lighting will cause light decay of LEDs or lasers, and the luminous brightness will decrease, affecting the lighting effect. The prior art reduces the possibility of light decay by enhancing the heat dissipation capacity of the cold light source and maintaining a stable temperature. However, the cause of light decay is not entirely temperature. The manufacturing processes and self-aging of LED chips or laser chips also affect light decay.

[0004] Therefore, it is necessary to automatically calibrate the cold light source, automatically compensate the light power when light power attenuation occurs, and give a prompt when the compensation upper limit is reached. Summary of the Invention

[0005] To solve the individual differences of cold light sources and reduce the influence of light decay on the performance of cold light sources, the present invention provides a method for automatically calibrating and compensating the light output power of an endoscope cold light source, which can reduce the differences between different batches of cold light sources, improve the service life of cold light source products, dynamically monitor and compensate for light source attenuation, and give a prompt when the compensation upper limit is reached. The specific solution is as follows.

[0006] A method for automatically calibrating the light output power before leaving the factory and automatically compensating the light output power during the use of an endoscope cold light source, characterized in that the automatic calibration of the light output power before leaving the factory includes the following steps:

[0007] Step S1: According to the characteristics of the selected light source and the light source efficiency, obtain the target approximate relationship formula between the light power value and the driving current , where P is the light power value at the light output port, I is the driving current value, and a, b, and c are all constants, and determine the light power tolerance E P , E P is the allowable light power error range of ±0.05 W;

[0008] Step S2: Determine the segmented drive current value I used by the cold light source according to the target approximation relationship formula in combination with the optical power requirement. N Create a list of (N = 1, 2, 3, ……) and save the list to the cold light source.

[0009] Step S3: Calculate the target optical power value P corresponding to the drive current I. N And measure the optical power measurement value P' at the light output port of the cold light source corresponding to the drive current I. N N N ;

[0010] Step S4: Calculate the difference E between the optical power measurement value P' and the target optical power value P, i.e., P' - P = E. If |E| ≤ |E|, no drive current adjustment is required; if |E| > |E|, automatic calibration is needed to re-determine the actual approximation relationship formula between the optical power value and the drive current, re-calculate the list of drive current values I', and save it to the cold light source. N N N N PN PN P PN P N

[0011] Step S5: Read the target feedback value S of the feedback module corresponding to each gear drive current I in the cold light source, and determine the approximation relationship formula S = aI² + bI + c, where S is the feedback value measured by the internal feedback module of the cold light source, I is the drive current, and a, b, and c are all coefficients. Save the formula to the cold light source to complete the automatic calibration. N N

[0012] The method for automatic compensation of the light output power during use includes the following steps:

[0013] Step T1: The cold light source reads the target feedback value S of the feedback module corresponding to the drive current I in the list and the actually measured feedback value S', and determines the feedback attenuation coefficient n. N N N

[0014] Step T2: If S' < nS, perform automatic compensation. According to the difference between the actually measured feedback value S' and the target feedback value S, i.e., S' - S = E. N N N N N N ​S , recalculate the approximate relationship formula between the feedback value of the attenuated feedback module and the drive current, that is , where c' = c + E S ;

[0015] Step T3: According to the approximate relationship formula obtained in Step T2, recalculate the drive current I' N for each gear, and save it to a new list;

[0016] Step T4: If the drive current has reached the maximum value I max , then save the list of drive current values for each gear at this time, and give a prompt to perform equipment maintenance in time to complete the automatic compensation.

[0017] The positive effects of the present invention are as follows:

[0018] 1. The method provided by the present invention automatically calibrates the optical power value before leaving the factory, greatly reducing the measurement time, and can be applicable to light sources with large individual differences, and making the final output optical power of the cold light source consistent.

[0019] 2. The method provided by the present invention can dynamically monitor the output optical power during use, and automatically compensate the output optical power when the optical power decays, reducing the influence of the optical power decay caused by long-term use on the performance of the cold light source product. Brief Description of the Drawings

[0020] Figure 1 is the flowchart of the method for automatically calibrating the output optical power of the endoscope cold light source in the present invention.

[0021] Figure 2 is the flowchart of the method for automatically compensating the output optical power of the endoscope cold light source in the present invention. Detailed Embodiment

[0022] Now, in combination with specific implementation examples and with reference to the drawings, the present invention will be further described in detail.

[0023] A method for automatically calibrating and automatically compensating the output optical power of an endoscope cold light source includes two parts: automatically calibrating the output optical power before leaving the factory and automatically compensating the output optical power during use. This implementation example automatically calibrates the output optical power of the endoscope cold light source with fluorescence function before leaving the factory and automatically compensates the optical power during use, including two light sources: white LED and Vcsel, and has the same steps as the content of the invention. To avoid repetition, only the key steps are described:

[0024] Specifically, during the automatic calibration of the output optical power before leaving the factory,

[0025] Step S1: According to the characteristics of the selected light source and the light source efficiency, the approximate relationship formula between the optical power value at the output port of the Vcsel and the driving current is P = -0.01I 2 + 0.96I - 1.72, and the approximate relationship formula between the optical power value at the output port of the white LED and the driving current is P = -0.0228I 2 + 0.3426I + 0.0598. The determined tolerance E of the optical power value P is ±0.05W.

[0026] Step S2: Combining the optical power requirements, determine the driving current value I used for the cold light source N (N = 1, 2, 3,... 10) list. For the white LED and Vcsel, ten gears are respectively determined, and the list is saved in the cold light source.

[0027] Step S4: The Vcsel in this embodiment needs to be automatically calibrated. The actual approximate relationship formula between the recalculated optical power value at the output port of the Vcsel and the driving current is P = -0.03I 2 + 1.11I - 1.51. Recalculate the list of ten - gear driving current values I N and save the list in the cold light source.

[0028] Step S5: The approximate relationship formula between the feedback value of the white LED measured by the cold light source feedback module and the driving current value is S = -351I 2 + 4439.8I + 982.77, and the approximate relationship formula between the feedback value of the Vcsel and the driving current value is S = 0.02I 2 - 0.06I + 0.05. Save the approximate relationship formula in the cold light source.

[0029] During the automatic compensation of the light output power during use,

[0030] Step T1: The determined feedback attenuation coefficient n is 70%.

[0031] Step T2: The difference E of the white LED S is 1775, and the difference E of the Vcsel S is 0.22. Recalculate the relationship formula between the attenuated feedback value and the driving current. The relationship formula for the white LED is S = -351I 2 + 4439.8I + 2757.77, and the relationship formula for the Vcsel is S = 0.02I 2 - 0.06I + 0.87.

[0032] A method for automatically calibrating the light output power and automatically compensating the light output power of an endoscope cold light source. By using the approximate relationship formula between the obtained light power value and the driving current, the determination of the list of segmented driving current values is completed, and the approximate relationship formula between the target feedback value of the feedback module and the driving current is obtained to complete the automatic calibration, so that the light output power value of the cold light source is within the tolerance range, ensuring the consistency of the cold light source. During use, the light output power is dynamically monitored through the feedback module. When the feedback value decays, by recalculating the approximate relationship formula between the feedback value of the feedback module and the driving current, the automatic compensation of the light output power is carried out, and the light output power value is adjusted to meet the requirements of the feedback attenuation coefficient with the factory automatic calibration value, ensuring the light output stability during the use of the cold light source and improving the quality of the cold light source.

Claims

1. A method for automatically calibrating and compensating the light output power of an endoscope cold light source, characterized in that The steps for automatic calibration of the output optical power before leaving the factory are as follows: Step S1: Obtain the target approximate relationship formula between the optical power value and the driving current according to the characteristics of the selected light source and the light source efficiency , where P is the optical power value at the light output port, I is the driving current value, and a, b, and c are all constants, and determine the tolerance E of the optical power value P , E P is the allowable optical power error range of ±0.05 W; Step S2: Determine the segmented drive current value I used for the cold light source according to the target approximation relationship formula and in combination with the optical power requirement N List of, N = 1, 2, 3,..., and save the list to the cold light source Step S3: Calculate the drive current I N The corresponding target optical power value P N , and measure the drive current I N The measured optical power value P' at the light output port of the cold light source corresponding to it N ; Step S4: Calculate the measured optical power value P' N and the target optical power value P N The difference P' N - P N = E PN , if |E PN | ≤ |E P |, then no drive current adjustment is performed; if |E PN | > |E P |, then automatic calibration is required to re-determine the actual approximate relationship formula between the optical power value and the drive current , re-calculate the list of drive current values I' N and save it to the cold light source; Step S5: Read the drive current I of each gear in the cold light source N The corresponding target feedback value S of the feedback module N , and determine the approximate relationship formula , where S is the feedback value measured by the feedback module inside the cold light source, I is the drive current, and a, b, and c are all coefficients. Save the formula in the cold light source to complete the automatic calibration; The method for automatic compensation of the output optical power during use includes the following steps: Step T1: The cold light source reads the drive current I in the list N The target feedback value S of the corresponding feedback module N and the actually measured feedback value S' N , and determine the feedback attenuation coefficient n; Step T2: If S' N < S N n, then perform automatic compensation. According to the actually measured feedback value S' N and the target feedback value S N the difference between them, that is, S' N - S N = E S , recalculate to obtain the approximate relationship formula between the feedback value of the attenuated feedback module and the drive current, that is , where c' = c + E S ; Step T3: Recalculate the drive current I' of each gear according to the approximate relationship formula obtained in Step T2 N and save the values into a new list; Step T4: If the drive current has reached the maximum value I max , then save the list of drive current values for each gear at this time, and give a prompt to perform equipment maintenance in a timely manner to complete the automatic compensation.

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