Multi-dimensional calibration method and system based on ambient light compensation and optimization

Abstract

The invention discloses a multi-dimensional calibration method and system based on ambient light compensation and optimization, belongs to the technical field of optical power measurement, and is suitable for power monitoring and calibration in an optical communication system. The method is used for calibrating three or more than three standard light sources with known power. Through a multi-dimensional calibration technology based on ambient light compensation and optimization of a self-adaptive compensation coefficient k, the measurement precision in a complex environment is significantly improved. The ambient light compensation module monitors the intensity and temperature of ambient light in real time, considers the aging factor of equipment, and calculates an adaptive compensation coefficient k, thereby achieving the dynamic adjustment of external interference. The multi-dimensional calibration adopts more than three standard light sources to carry out multi-point nonlinear fitting, a compensated optical power value is calculated in combination with a calibration formula, and a measurement error in a high power range is optimized.

Description

Technical Field

[0001] The present invention discloses a high-precision optical power meter and its calibration compensation method, belonging to the technical field of optical power measurement, and applicable to power monitoring and calibration in optical communication systems. It is particularly applicable to high-precision measurement of optical power in complex environments. Background Art

[0002] The existing calibration methods for optical power meters mainly rely on the measurement of a single standard light source and linear fitting models. Usually, only the errors in power measurement itself are considered, while the influence of factors such as ambient light on the measurement results is ignored. In addition, the traditional calibration methods have limited error compensation for high power ranges, often resulting in insufficient measurement accuracy and unable to meet the requirements for high-precision measurement. With the continuous expansion of the application fields of optical power meters, especially in complex industrial, scientific research, and medical detection environments, the limitations of traditional methods are gradually emerging. Therefore, how to improve the calibration accuracy of optical power meters and enhance their adaptability has become an urgent technical problem to be solved. Summary of the Invention

[0003] In view of the problems existing in the prior art, the present invention provides a multi-dimensional calibration method based on ambient light compensation and optimization, and the method is applied to the measurement of high-power optical power meters above 10 mW;

[0004] The method is to calibrate three or more standard light sources with known powers using an optical power meter, and the calibration formula is:

[0005]

[0006] where a i and b are calibration coefficients obtained by multi-point calibration fitting, P i corrected is the i-th optical power value after ambient light compensation, and P calibrated is the optical power value after calibration.

[0007] The present invention also provides a multi-dimensional calibration method based on ambient light compensation and optimization. The method is to calibrate a standard light source using an optical power meter, and the calibration formula is:

[0008] P corrected = P measured - k(E ambient , T, λ)·E ambient ,

[0009] where E ambient is the ambient light intensity, P measured is the measured optical power, T is the temperature coefficient, λ is the device aging coefficient, and k is the adaptive compensation coefficient;

[0010] The calculation formula for the adaptive compensation coefficient k is as follows:

[0011] k = k 0 + α·(E ambient - E 0 ) + β·(T - T 0 ) + γ·λ,

[0012] where, K 0 is the initial compensation coefficient; E 0 is the standard ambient light intensity during calibration; T 0 is the standard temperature during calibration; α, β, γ are coefficients obtained through experimental calibration, reflecting the influence of ambient light, temperature, and aging on k.

[0013] Preferably, T 0 is specifically 25 °C.

[0014] Preferably, λ is specifically the number of years of equipment aging.

[0015] Preferably, k 0 = 0.02; E 0 = 0.05.

[0016] Another aspect of the present invention is to provide a system for multi-dimensional calibration of ambient light compensation and optimization. The system uses the above calibration method for multi-dimensional calibration of ambient light compensation and optimization.

[0017] Compared with the prior art solutions, the present invention has at least the following beneficial effects:

[0018] 1. The present invention innovatively proposes a multi-dimensional calibration method for ambient light compensation and optimization based on the adaptive compensation coefficient K. By introducing an adaptive compensation factor, a non-linear calibration function, and an enhanced error model, this method achieves high-precision measurement compensation for optical power meters in complex environments. Especially in the high-power range, this method can dynamically adjust the compensation coefficient K to overcome the error limitations of traditional linear fitting methods, thereby significantly improving the accuracy and reliability of measurements.

[0019] 2. Through the multi-dimensional calibration method for ambient light compensation and optimization by introducing the adaptive compensation coefficient K, the optical power meter of the present invention can provide higher-precision optical power measurements, especially showing significant advantages in different power ranges. This method overcomes the limitations of traditional optical power meter calibration methods in complex environments. It can not only automatically adapt to changes in ambient light, temperature, and equipment aging, but also dynamically adjust compensation parameters during the measurement process to ensure high precision and high stability of the measurement results. In addition, the present invention has stronger environmental adaptability and can perform intelligent adjustments for different types of light sources and measurement scenarios to meet various measurement requirements, and is applicable to the field of high-precision optical measurements. Description of the Drawings

[0020] Figure 1 Error comparison chart between the traditional method and the present invention;

[0021] Figure 2 Comparison of compensation effects under varying ambient light intensities.

[0022] The present invention will be further described in detail below. However, the following examples are merely simple examples of the present invention and do not represent or limit the scope of the claimed rights of the present invention. The scope of protection of the present invention shall be subject to the claims. Specific embodiments

[0023] The technical solution of the present invention will be further described below in conjunction with the accompanying drawings and through specific embodiments.

[0024] Embodiment 1: Ambient light compensation with an adaptive compensation coefficient k.

[0025] Ambient light compensation is achieved by setting an ambient light detection module near the measurement path of the optical power meter. This module continuously monitors and detects the light intensity in the measurement environment. E ambient , and then compensation is performed based on this value to eliminate the measurement error caused by external ambient light interference. The compensation coefficient k is obtained through experimental calibration and is linearly related to the ambient light intensity E ambient . Usually, k is optimized through measurements under different ambient light conditions. In addition, the present invention creatively introduces an adaptive compensation coefficient, using a dynamically calculated compensation coefficient k(E ambient , T, λ), making it related not only to the ambient light E ambient but also considering the effects of temperature T and device aging λ. The compensation model is trained with historical measurement data to make the k value vary with environmental factors and optimize the optical power compensation accuracy.

[0026] P corrected = P measured - k(E ambient , T, λ) · E ambient

[0027] Among them, the adaptive compensation coefficient k is dynamically calculated using machine learning methods to improve the compensation accuracy.

[0028] The key here is how to calculate the adaptive compensation coefficient k. The adaptive compensation coefficient k is determined by the following factors:

[0029] 1. Ambient light intensity E ambient ;

[0030] 2. Temperature effect T: The sensor of the optical power meter is affected by temperature. The higher the temperature, the more likely the response of the photosensitive element will drift.

[0031] 3. The aging of the device affects λ: Long-term use results in a decrease in the sensitivity of the sensor, affecting the measurement accuracy.

[0032] The calculation formula for the adaptive compensation coefficient is obtained through experiments and data fitting as follows:

[0033] k = k 0 +α·(E ambient -E 0 )+β·(T - T 0 )+γ·λ

[0034] Where:

[0035] K 0 is the initial compensation coefficient (calibrated under standard conditions);

[0036] E 0 is the standard ambient light intensity during calibration;

[0037] T 0 is the standard temperature during calibration (such as 25 °C);

[0038] α, β, γ are coefficients calibrated through experiments, reflecting the effects of ambient light, temperature, and aging on k.

[0039] Suppose the measurement conditions are as follows:

[0040] Ambient light intensity: E ambient = 0.1 mW / cm 2 ; Current temperature: T = 30 °C; Device aging time: λ = 2 years.

[0041] Calculate the compensation coefficient according to the above formula:

[0042] k = 0.02 + 0.003*(0.1 - 0.05) + 0.001*(30 - 25) + 0.005*2 = 0.03515

[0043] Then perform the compensation calculation:

[0044] Suppose the value measured by the optical power meter is: Measured optical power: P measured = 5.0 mW;

[0045] According to the compensation formula:

[0046] P corrected = P measured -k(E ambient ,T,λ)·E ambient

[0047] Substitute the above data to get: P corrected = 5.0 - 0.03515*0.1 = 4.9965 mW.

[0048] Result analysis:

[0049] The compensation value calculated according to the traditional method (fixed k = 0.02) is 4.998 mW.

[0050] By the method of the present invention, the compensation value calculated by adding the adaptive compensation method is 4.9965 mW, and the relative error is reduced by three ten-thousandths. Although the value is small, this is particularly important in high-precision measurements.

[0051] Traditional fixed compensation methods are usually based on laboratory calibration data and cannot adapt to complex environmental changes, such as the drift after long-term use of a optical power meter or the influence of environmental temperature.

[0052] After introducing k, the compensation amount will be adjusted according to changes in the external environment. For example, in a high-temperature environment, the sensitivity of the photodetector may decrease. At this time, k will automatically adjust the compensation amount to reduce errors. Temperature drift compensation to ensure long-term stability. The response of the photodetector will drift with temperature changes, affecting the measurement accuracy. By monitoring the environmental temperature through a temperature sensor and dynamically adjusting the measurement compensation in combination with k, the influence of temperature on the measurement result can be effectively reduced.

[0053] Enhanced environmental light adaptability and reduced external interference. Under complex lighting conditions, such as changes in natural light sources and interference from fluorescent lamps, the measured values are prone to deviation. The adaptive compensation coefficient K can be dynamically adjusted according to different environmental light intensities to ensure that external interference is effectively removed.

[0054] In addition, equipment aging compensation is also considered to extend the service life of the instrument: Since the performance of the detector and optical system will decay after long-term use, traditional methods require regular manual recalibration. After adopting K, the compensation strategy can be automatically adjusted by real-time monitoring of the equipment status, reducing the manual maintenance cost and increasing the service life of the equipment.

[0055] In summary, an adaptive compensation coefficient K is introduced for environmental light compensation here. By using the adaptive compensation coefficient, the compensation can be dynamically adjusted according to factors such as environmental light, temperature, and equipment aging, improving the measurement accuracy. This method is applicable to high-precision optical power meters, especially in complex environments, and can effectively reduce errors.

[0056] Embodiment 2: A method for optical power measurement based on an adaptive compensation coefficient and multi-dimensional calibration.

[0057] Optical power measurement is crucial in precision optical systems. However, factors such as environmental light changes, temperature drift, and sensor aging will affect the measurement accuracy. In addition, the optical power meter itself may have nonlinear errors and requires further calibration. This embodiment combines an adaptive compensation coefficient for environmental light compensation and uses multi-dimensional calibration for final correction to improve the measurement accuracy.

[0058] The multi-dimensional calibration formula among them is

[0059]

[0060] When measuring the unknown optical power, first perform ambient light compensation to obtain P corrected , and then calculate the finally calibrated optical power value according to the calibration formula.

[0061] The symbol explanations of the above formula are as follows:

[0062] P calibrated : The calibrated optical power value, that is, the final measurement result after compensation and correction. P corrected : The optical power measurement value after ambient light compensation, removing the influence of ambient light. Polynomial calibration corrects the systematic error by fitting power terms of different orders P i corrected to.

[0063] a i : The coefficient of polynomial fitting, representing the calibration weights of different orders.

[0064] i: The index of the polynomial order, indicating the i-th order calibration term.

[0065] n: The highest order of the polynomial, determining the complexity of the fitting.

[0066] b: The constant term, representing the reference offset compensation of the system, which can further adjust the measurement reference.

[0067] This method improves the measurement accuracy through multi-dimensional calibration and is applicable to the error correction of optical power meters.

[0068] Ambient light compensation calculation:

[0069] The calculation formula for the adaptive compensation coefficient k is:

[0070] k = k 0 + α·(E ambient - E 0 ) + β·(T - T 0 ) + γ·λ

[0071] Among them:

[0072] k 0 = 0.02 mW / (mW / cm 2 )(initial compensation coefficient); E 0 = 0.05 mW / cm 2 (ambient light intensity during calibration); T 0= 25 °C (temperature during calibration); α = 0.003 mW / (mW / cm2) (ambient light influence coefficient); β = 0.001 mW / (mW / cm 2 ) / °C) (temperature influence coefficient); γ = 0.005 mW / (mW / cm 2 ) / year (aging influence coefficient);

[0073] Known conditions:

[0074] Ambient light intensity E ambient = 0.1 mW / cm2; Current temperature T = 30 °C; Equipment aging time λ = 2 years; From the above data and formula, the adaptive compensation coefficient k = 0.03515 mW / (mW / cm2)

[0075] Measured optical power P measured = 5.0 mW; Optical power P after compensation corrected = 4.9965 mW; The calculation methods and values used above are the same as those in Example 1.

[0076] Next, perform multi-dimensional calibration calculations:

[0077] Calibrate using three standard light sources with known powers:

[0078] Standard optical power: P std1 = 1.0 mW, P std2 = 5.0 mW, P std3 = 10.0 mW

[0079] Measured values: P measured1 = 0.98 mW, P measured2 = 4.95 mW, P measured3 = 9.90 mW

[0080] Error calculation:

[0081] ⊿P1 = 1.0 - 0.98 = 0.02 mW

[0082] ⊿P2 = 5.0 - 4.95 = 0.05 mW

[0083] ⊿P3 = 10.0 - 9.90 = 0.1 mW

[0084] (1) Fitting calibration coefficient

[0085] Using the polynomial fitting method, the calibration formula is obtained:

[0086]

[0087] The fitting coefficients obtained from the experiment: coefficient of the first-order term: a1 = 1.02; coefficient of the second-order term: a2 = -0.03; constant term: b = 0.05.

[0088] (2) Calculate the finally corrected optical power

[0089] Substitute P corrected = 4.9965 mW into the calibration formula:

[0090] P final = 1.02 * 4.9965 + (-0.03) * (4.9965) 2 + 0.05 = 4.99745 mW.

[0091] In the overall calibration process combining the above two calibration processes, the calibration process of the optical power meter includes two important steps:

[0092] (1) Ambient light compensation based on the adaptive compensation coefficient K: By introducing the adaptive compensation coefficient K, the compensation amount is dynamically adjusted to adapt to different ambient light conditions, temperature changes, equipment aging and other factors, reduce the interference of external light sources, and ensure the accuracy and stability of the measurement.

[0093] (2) Multi-dimensional calibration: Adopt the method of multi-point data fitting to calculate the optimal calibration coefficients, and correct them in combination with the compensated optical power value, so that the final measurement result is closer to the true value and improve the measurement accuracy.

[0094] By combining the ambient light compensation and multi-dimensional calibration technologies, the present invention can effectively improve the measurement accuracy and stability of the optical power meter, reduce the errors caused by environmental changes and instrument aging, make the optical power meter more reliable in actual use, and be applicable to more complex measurement environments.

[0095] Technical effects compared with traditional methods:

[0096] In the conventional calibration of the optical power meter, it is assumed that a single standard light source is used for calibration. The traditional method uses a linear fitting model, with a known power P std = 5.0 mW of a standard light source, and the measured optical power P measured = 4.98 mW, and the calibration coefficients a = 1.005 and constant b = -0.02 are obtained through linear fitting. The optical power value obtained according to the traditional calibration method is:

[0097] Ptraditionally = 1.005 × Pmeasured - 0.02 = 1.005 × 4.98 - 0.02 = 5.0 mW

[0098] However, in the actual environment, interferences including ambient light often cause large deviations in the measurement results, especially in the high-power range.

[0099] However, by adopting the method of the present invention, through real-time ambient light compensation and multi-dimensional calibration based on the adaptive compensation coefficient K, these deviations can be significantly reduced. For example, in an actual test with a relatively high ambient light intensity, the optical power measured by the traditional method was 5.0 mW, while the present invention obtained approximately 4.99745 mW after compensation, further improving the accuracy compared to the traditional method.

[0100] Embodiment 3: Application in high-power measurement

[0101] Suppose during high-power measurement (for example, above 10 mW), due to the interference of ambient light and the superposition of measurement errors, the traditional method often leads to relatively large errors, possibly deviating from the standard power value by 0.1 mW. However, through optimized multi-dimensional calibration and ambient light compensation, the present invention can still maintain high accuracy within the high-power range. In this case, the error between the optical power value measured by the method of the present invention and the actual value is only 0.02 mW, and the accuracy is improved by approximately 3 times.

[0102] To more intuitively demonstrate the technical advantages of the present invention compared to the traditional method, the following shows the error comparison under different optical power ranges and ambient light intensities in the form of tables and charts. First, starting from the error comparison within the optical power range, it focuses on showing the error changes of the traditional method and the present invention under different power conditions.

[0103] Table 1: Error comparison between the present invention and the traditional method in different optical power ranges

[0104] Optical power range (mW) Error of traditional method (mW) Error of the present invention (mW) Error improvement (mW) Improvement percentage 1.0 0.02 0.01 0.01 50％ 5.0 0.05 0.02 0.03 60％ 10.0 0.10 0.02 0.08 80％

[0105] As shown in Table 1, within different optical power ranges, the present invention has obvious error improvement compared to the traditional method. As the optical power increases, the amplitude of error improvement gradually expands. Next, through Chart 1, we will more intuitively show this error difference to help further analyze the technical effects of the present invention.

[0106] Table 2: Comparison of ambient light compensation effects of different calibration methods

[0107]

[0108] The preferred embodiments of the present invention have been described in detail above. However, the present invention is not limited to the specific details in the above embodiments. Within the technical concept of the present invention, various simple modifications can be made to the technical solutions of the present invention, and these simple modifications all fall within the protection scope of the present invention.

[0109] In addition, it should be noted that, among the various specific technical features described in the above specific embodiments, they can be combined in any appropriate manner without conflict. To avoid unnecessary repetition, the present invention will not separately describe various possible combination methods.

[0110] Furthermore, any combinations can be made among various different embodiments of the present invention, as long as they do not violate the idea of the present invention, and they should also be regarded as the content disclosed by the present invention.

Claims

1. A multi-dimensional calibration method based on ambient light compensation and optimization, characterized in that: The method is applied to high-power optical power meter measurement above 10mW; The method is to use an optical power meter to calibrate three or more standard light sources with known power, and the calibration formula is: Among them, a i and b are the calibration coefficients obtained from multi-point calibration fitting, P i corrected is the light power value of the ith light after ambient light compensation, P calibrated is the optical power value after calibration.

2. A multi-dimensional calibration method based on ambient light compensation and optimization, characterized in that: The method is to use an optical power meter to calibrate the standard light source, and the calibration formula is: P corrected =P measured -k(E ambient ,T,λ)·E ambient , Among them, E ambient is the ambient light intensity, P measured is the measured optical power, T is the temperature coefficient, λ is the equipment aging coefficient, and k is the adaptive compensation coefficient; The calculation formula of the adaptive compensation coefficient k is as follows: k=k0+α·(E ambient -E0)+β·(T-T0)+γ·λ, Among them, K0 is the initial compensation coefficient; E0 is the standard ambient light intensity during calibration; T0 is the standard temperature during calibration; α, β, γ are experimental calibration coefficients, reflecting the effects of ambient light, temperature and aging on k.

3. The method according to claim 2, characterized in that: Specifically, T0 is 25°C.

4. The method according to claim 2, characterized in that: λ is specifically the number of years of equipment aging.

5. A system for multi-dimensional calibration that performs ambient light compensation and optimization according to the methods of claims 1-4.

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