High-Precision Temperature Control of Laser Crystals

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

The authors developed a high-precision temperature control oven for LBO crystals for SHG. It is well organized and written，so I suggest accepting it after the minor issues are addressed.

 

1.     How do you determine the temperature fluctuation within ±0.009? Is it he deference between maximum and minimum?

2.     Why you set the working temperature at 101 ℃？

3.     Could you specify the parameters of PID for readers?

4.     A relevant paper about the temperature control of laser system should be cited in the introduction “Rew. Sci. Instrum. 89, 103103 (2018)”.

Author Response

Comments 1: How do you determine the temperature fluctuation within ±0.009? Is it he deference between maximum and minimum?

Response 1:We thank the reviewer for pointing out these problems. As you mentioned, the temperature fluctuation within ±0.009 refers to the variation from the maximum to the minimum value. We have modified the wording of line 197.

Comments 2: Why you set the working temperature at 101 ℃?

Response 2: We are grateful to the reviewer for bringing this omission to our attention. The crystal has a cut angle of 12° and a phase-matching temperature of 70°C. By rotating the crystal angle, we can change its phase-matching temperature. During the tuning process, we found that when the crystal angle was adjusted so that the phase-matching temperature was around 101°C, the SHG efficiency was highest. Therefore, we decided to operate the temperature control oven in this state. We have, accordingly, added these explanations from line 190 to line 194.

Comments 3: Could you specify the parameters of PID for readers?

Response 3: We apologize for the oversight regarding the specifics of the PID parameters. Of course, The detailed PID parameters are in the newly added paragraph on line 174.

Comments 4: A relevant paper about the temperature control of laser system should be cited in the introduction “Rew. Sci. Instrum. 89, 103103 (2018)”.

Response 4: We sincerely appreciate the valuable comments. This paper discusses the precise control of laser driver current and the control of laser operating temperature, and can serve as background information for laser system temperature control. It has been cited in the manuscript as reference number 13.

Reviewer 2 Report

Comments and Suggestions for Authors

This paper provides a detailed introduction to the research on high-precision laser crystal temperature control, particularly its application in second harmonic generation (SHG). The authors have developed a laser crystal oven that can control temperature fluctuations within ± 0.009 ℃, which is crucial for achieving stable and efficient SHG. The experimental results provided in the paper show that the power fluctuation of the system is only 0.7% at an average power of 13.7 W, indicating that their design achieves high accuracy and stability. However, there are still some problems to be solved.

1. Comparative analysis: The comparison with other works is not detailed enough, only briefly mentioning the usual level of accuracy. A more comprehensive comparison can help readers understand the advantages of the new design.

2. Long term stability testing: Although short-term stability is mentioned, long-term performance data is crucial for evaluating the reliability of the system.

3. Can the authors explain the high fluctuations in figure 8 (a) at 3-4 minutes?

Author Response

Comments 1: Comparative analysis: The comparison with other works is not detailed enough, only briefly mentioning the usual level of accuracy. A more comprehensive comparison can help readers understand the advantages of the new design.

Response 1: We thank the reviewer for these valuable comments. We have modified the introduction section, outlined the detail features of other works in line 54 to line 67. And in the discussion section, we have compared our work with others and emphasized the features of this design and its advantages compared to other works in line 238 to line 246.

Comments 2: Long term stability testing: Although short-term stability is mentioned, long-term performance data is crucial for evaluating the reliability of the system.

Response 2: We apologize for the oversight regarding the long-term performance. We have added the operating results (Figure 13) of the temperature control oven over a 9-day period in the paragraph on line 224

Comments 3: Can the authors explain the high fluctuations in figure 8 (a) at 3-4 minutes?

Response 3: We thank you for pointing this out. There was no laser passing through the LBO crystal for the first three minutes in the figure. Starting from the third minute, the infrared laser power was increased, and the heat deposition caused by the laser led to temperature fluctuations. This phenomenon is explained in line 208.