Oblique-Incidence Interferometric Measurement of Optical Surface Based on a Liquid-Crystal-on-Silicon Spatial Light Modulator
Round 1
Reviewer 1 Report (Previous Reviewer 1)
Comments and Suggestions for AuthorsThe authors responded to all my notes, made all the required corrections and added some extra material to improve the understanding of the paper. I believe it can be published now.
Author Response
Dear Reviewers:
We would like to express our sincere thanks for your constructive and positive comments on our manuscript.
Comment.1: The authors responded to all my notes, made all the required corrections and added some extra material to improve the understanding of the paper. I believe it can be published now.
Response: Thank you for your careful review and comments on the manuscript.
Once again, thank you very much for your suggestions.
Best regards,
Corresponding authors:
Zhen Zeng, zengzhen@hbut.edu.cn
Reviewer 2 Report (Previous Reviewer 2)
Comments and Suggestions for AuthorsThe manuscript can be accepted for publication for all my concerns have been addressed properly.
Comments on the Quality of English LanguagePlease check the capitalization of the first letters of some phrases in Fig.2, for example,"Optical system Alignment","Measured surface"
Author Response
Dear Reviewers:
We would like to express our sincere thanks for your constructive and positive comments on our manuscript. We have studied comments carefully and have made correction which we hope meet with approval. Revised portions are marked in red for easy tracking. The main corrections in the paper and the responds to the reviewer’s comments are as following:
Comment.1: Please check the capitalization of the first letters of some phrases in Fig.2, for example, "Optical system Alignment", "Measured surface".
Response: Thanks for your kind suggestion. We have revised these phrases in Figure 2 for better viewing.
Once again, thank you very much for your suggestions.
Best regards,
Corresponding authors:
Zhen Zeng, zengzhen@hbut.edu.cn
Reviewer 3 Report (New Reviewer)
Comments and Suggestions for AuthorsThe authors proposed a structure of optical path employing LC-based SLM at oblique incidence to get the wavefront and surface 80 information of optical lens and find a solution for the phase diagram calculation method for null interferometric test of optical surface. As a result of careful assessment, I conclude that several important issues require deeper discussion. Therefore, I am asking the authors to thoroughly address and discuss the issues listed below:
1. The authors completely omitted the role of LCs in spatial light modulators. There is not even a word about what liquid crystal material was used, what dielectric parameters it had, and what special properties of LCs make them play a leading role in this type of devices? In this regard, it is worth mentioning new types of LC mixtures that have been used in tunable photonic devices, i.e. Appl. Phys. Lett. 103, 172902 (2013); Appl. Phys. Lett. 102, 102904 (2013), Opt. Express 20, 364-376 (2012), etc.
2. Figure 5(a) in its current form is practically illegible.
3. What error is made during measurement the accuracy of the proposed interferometric system at oblique incidence? What methods can be used to significantly reduce it?\
4. The summary should be significantly expanded. The role of the described scheme and the specific applications of the presented model should be emphasized.
Comments on the Quality of English LanguageMinor editing of English language required.
Author Response
Dear Editors and Reviewers:
We would like to express our sincere thanks for your constructive and positive comments on our manuscript. We have studied comments carefully and have made correction which we hope meet with approval. Revised portions are marked in red for easy tracking. The main corrections in the paper and the responds to the reviewer’s comments are as following:
Comment.1: The authors completely omitted the role of LCs in spatial light modulators. There is not even a word about what liquid crystal material was used, what dielectric parameters it had, and what special properties of LCs make them play a leading role in this type of devices? In this regard, it is worth mentioning new types of LC mixtures that have been used in tunable photonic devices, i.e. Appl. Phys. Lett. 103, 172902 (2013); Appl. Phys. Lett. 102, 102904 (2013), Opt. Express 20, 364-376 (2012), etc.
Response: Thanks for your kind suggestion. The LCoS-SLM we used in the research is a phase-only SLM (Pluto-VIS, HOLOEYE Photonics AG, Germany). Its LC material is parallel nematic liquid crystal. We have added sentences and references about the role of LC according to your kind advice.
Comment.2 Figure 5(a) in its current form is practically illegible.
Response: We are sorry that this figure has caused some confusion to your understanding. We have added captions and explanations the ray-tracing procedure about the figure. The figure is plotted in the MATLAB program according to the ray tracing model shown in Figure 4. The light between the reference and the SLM are marked with green color. The light between the SLM and measured surface are marked with yellow color.
Comment.3 What error is made during measurement the accuracy of the proposed interferometric system at oblique incidence? What methods can be used to significantly reduce it?
Response: Thank you for point out this issue. We use a Twyman Green type interferometer in the measurement system, so after building the oblique incidence interferometric optical path proposed in the paper, a high-precision standard flat mirror (λ/20, λ=632.8 nm) should be used to calibrate the error of the optical system first with zero phase map loaded on the SLM. And secondly, the system needs a precise rotator stage to adjust the SLM head at the designed angle θ mentioned in Section 2. Thirdly, the nonlinearity and nonuniformity of SLM would also contribute to the wavefront error. The wavefront of SLM (zero phase) could be calibrated with compensation algorithms to better than λ/6 (λ=632.8 nm). We tried our best to reduce these errors during measurement to improve the accuracy of the proposed system at oblique incidence.
Comment.4 The summary should be significantly expanded. The role of the described scheme and the specific applications of the presented model should be emphasized.
Response: Thanks for your suggestion. We rephased the summary and added some discussions about the measurement accuracy and the specific applications such as the measurement and calibration process of the off-axis three-mirror anastigmat system.
Comment.5 Minor editing of English language required.
Response: Thank you for pointing out the writing problem of this manuscript. We have checked some incorrect English expression and revised them.
We tried our best to improve the manuscript and made some changes in the manuscript. These changes will not influence the main content and framework of the paper and be marked in red in revised paper.
We appreciate for Editors and Reviewers’ warm work earnestly, and hope that the correction will meet with approval.
Once again, thank you very much for your comments and suggestions.
Best regards,
Corresponding authors:
Zhen Zeng, zengzhen@hbut.edu.cn
This manuscript is a resubmission of an earlier submission. The following is a list of the peer review reports and author responses from that submission.
Round 1
Reviewer 1 Report
Comments and Suggestions for Authors Null interferometry at oblique incidence requires rather complex optical compensator which is usually done by static computer generated hologram or phase-only special light modulator. The setup alignment and the compensation phase map are time consuming. In this work a simple way to calculate the compensation matrix (ray tracing model) is proposed and tested on two examples. The alignment of an off-axis oblique incidence setup is also well described. Oblique geometry allows avoiding beam splitter in the light pass improving the quality of the interference pattern and increasing the measurement accuracy. The technique is important and timely and definitely requires careful attention. It perfectly fits the scope of the journal, would be of interest to others in the field and worth publishing. All the calculations and the experiment are well described with all the required details included. A few of corrections would be useful. I list then in order of appearance (not importance).
1. English requires some revision.
2. 13. “LCoS-SLM’s” possessive form better be avoided in formal writing
3. 74. Would be good to finish the introduction with a paragraph of what is done in the paper.
4. 77. “commercial interferometer” which one? A reference?
5. 104 “problem could be improved”
6. 105 “the cost is expensive”
7. 107 “with as less optical” all three could be rephrased with better English
8. 126 “in the model, the…” in the model: the … semicolon would be better
9. 130 “The optical path in the actual optical path” rephrasing
10. 133 “V points are defined by the T points” the points are not introduced yet, only the surfaces
11. 147 “it becomes” It is the beginning of a paragraph. What is “it”?
12. 167 “the spherical wavefront measurement results of 0.117lambda” what is 0.117lambda? PV? PV is not introduced yet.
13. 175 “with a radius of 50000 mm and a diameter of 30 mm” sounds strange, requires rephrasing
14. 184 PV requires introduction
Comments on the Quality of English LanguageIncluded in comments to the authors
Author Response
Dear Editors and Reviewers:
We would like to express our sincere thanks for your constructive and positive comments on our manuscript. We have studied comments carefully and have made correction which we hope meet with approval. Revised portions are marked in red for easy tracking. The main corrections in the paper and the responds to the reviewer’s comments are as following:
Reviewer #1
Thank you for your careful review and comments in the manuscript. Firstly, thank you for your recognition of our research. In view of the language problem that you pointed out, we have checked the writing grammars in detail throughout the article and revised them. Besides, we have provided more discussion in the finish paragraph of the introduction to enrich the background research. Then, based on the three amendments you suggested, we thought about it carefully and responded and revised them.
Comment.1: English requires some revision.
Response: Thank you for your careful work on this issue., we have corrected language problem that you pointed out and checked the writing grammars in detail throughout the article and revised them.
Comment.2: 13. “LCoS-SLM’s” possessive form better be avoided in formal writing.
Response: The expression of the sentence has been rephrased.
Comment.3: 74. Would be good to finish the introduction with a paragraph of what is done in the paper.
Response: Thanks for your kind suggestion. A paragraph about the key idea of the research has been added at the end of the introduction.
Comment.4: 77. “commercial interferometer” which one? A reference?
Response: The commercial interferometer used in the research is µPhase 1000, Fisba Optik, TRIOPTICS GmbH, Germany, with an accuracy of λ/20 PV (peak to valley), λ=632.8nm. The latest version is µPhase 3. And we add a reference of this interferometer.
Comment.5: 104 “problem could be improved”
Response: We apologize for the misunderstanding caused by our English expression. The problem refers to the disturbed pattern in normal incidence optical setup. We correct the expression of this sentence.
Comment.6: 105 “the cost is expensive”
Response: Thanks for point out this issue. The meaning to the expression is that the cost of coating and special processing of the beam splitting prism is very high and time consuming. We replace the expression.
Comment.7: 107 “with as less optical” all three could be rephrased with better English
Response: Thanks for your suggestion. We rephrase the words with minimum number of optical components.
Comment.8: 126 “in the model, the…” in the model: the … semicolon would be better
Response: Thanks for your kind comment. We used semicolon instead of comma.
Comment.9: 130 “The optical path in the actual optical path” rephrasing
Response: Thank you for pointing out the English writing problem. We revised the sentence. The surface order that light travels in the optical path is “M-S-R”.
Comment.10: 133 “V points are defined by the T points” the points are not introduced yet, only the surfaces
Response: Thank you for pointing out the problem in our English writing. We revised the manuscript and corrected coordinate point expression. For example, we used V surface and Vn to express the surface and the point on it.
Comment.11: 147 “it becomes” It is the beginning of a paragraph. What is “it”?
Response: We are sorry for the incorrect English expression. It refers to the calculation of points coordinates of surface T and V. We have revised this sentence.
Comment.12: 167 “the spherical wavefront measurement results of 0.117lambda” what is 0.117lambda? PV? PV is not introduced yet.
Response: Thank you for point out the improper use of wavelength symbol. The lambda (λ) refers to the wavelength of laser, which is 632.8nm, and we added it in the revised manuscript. The PV (peak to valley) has been added after the abbreviation.
Comment.13: 175 “with a radius of 50000 mm and a diameter of 30 mm” sounds strange, requires rephrasing.
Response: We are sorry that this expression has caused some confusion to your understanding. We rewrote the expression of this text marked in red. The purpose of using a spherical surface with large radius of curvature is that this gentle concave sphere surface could be measured directly by the interferometer with a planar objective lens to get the reference value for comparison with the proposed optical setup at oblique incidence.
Comment.14: 184 PV requires introduction.
Response: Thank you for pointing out the shortcomings of this abbreviation. The PV (peak to valley) has been added.
We tried our best to improve the manuscript and made some changes in the manuscript. These changes will not influence the main content and framework of the paper and be marked in red in revised paper.
We appreciate for Editors and Reviewers’ warm work earnestly, and hope that the correction will meet with approval.
Once again, thank you very much for your comments and suggestions.
Best regards,
Corresponding authors:
Zhen Zeng, zengzhen@hbut.edu.cn
Reviewer 2 Report
Comments and Suggestions for AuthorsIn this manuscript，An oblique incidence interferometric measurement and alignment method is proposed to measure and adjust optical surfaces with a LCoS-SLM. It could reduce the measuring cost and time consumption due to the LCoS-SLM’s programmable function and offer the ability to align the optical system. Firstly, the off-axis paraboloid model is used to apply the LCoS-SLM as a phase compensator to generate a focusing spot or light spots array to adjust the measured optical surface. Then, the calculated compensation phase map from ray tracing calculation is loaded on the LCoS-SLM without any mechanical adjustment to achieve measurement. And two typical optical surfaces were measured to verify the accuracy of the proposed system.
The manuscript is well written, I have two small advice.
1. According to Figure 2b, it will better to introduce the optical alignment and optical surface measurement process in detail.
2. Comparing to reference 23, what is new idea of this work? It will be better to make it clear.
Comments on the Quality of English LanguageIt is good.
Author Response
Dear Editors and Reviewers:
We would like to express our sincere thanks for your constructive and positive comments on our manuscript. We have studied comments carefully and have made correction which we hope meet with approval. Revised portions are marked in red for easy tracking. The main corrections in the paper and the responds to the reviewer’s comments are as following:
Reviewer #2
Thank you for your careful review and comments in the manuscript. Firstly, thank you for your recognition of our research. In view of the language problem that you pointed out, we have checked the writing grammars in detail throughout the article and revised them. Besides, we have provided more discussion in the finish paragraph of the introduction to enrich the background research. Then, based on the three amendments you suggested, we thought about it carefully and responded and revised them.
Comment.1: According to Figure 2b, it will better to introduce the optical alignment and optical surface measurement process in detail.
Response: Thank you for your kind suggestion. We added some sentences on how to use the generated focusing spot array for angle and position adjustment of the optical setup.
Comment.2: Comparing to reference 23, what is new idea of this work? It will be better to make it clear.
Response: Thank you for point out this issue. Reference 23 is our prior research, which presented the experiment effect of using focused light array generated by SLM to align the optical path. It is one part of the preliminary work of this research. The research work needs more Mathematical models, optical tracing to get the measurement phase map, which is not reported in reference 23. Our proposed manuscript is to propose a simple structure of optical path at oblique incidence to get the wavefront and surface information of optical lens and find a solution for the phase diagram calculation method both for measurement and alignment.
We tried our best to improve the manuscript and made some changes in the manuscript. These changes will not influence the main content and framework of the paper and be marked in red in revised paper.
We appreciate for Editors and Reviewers’ warm work earnestly, and hope that the correction will meet with approval.
Once again, thank you very much for your comments and suggestions.
Best regards,
Corresponding authors:
Zhen Zeng, zengzhen@hbut.edu.cn
Reviewer 3 Report
Comments and Suggestions for AuthorsDear Authors,
It is recommended to expand your literature review. Ensure that you have explored all relevant research and literature in your field. Include related studies, theories, and prior developments that provide the appropriate context for your work.
If the proposed method and the use of LCOS have already been reported[1], it is essential to clearly highlight what distinguishes your approach. Are you introducing improvements, modifications, or unique applications? Ensure that your article emphasizes these distinctive aspects.
If you are using images that have been previously published, make sure to obtain the necessary permissions for their use and properly cite the original sources.
For your work to be considered for publication, you must present a significant new contribution to the field. This may involve enhancements to the existing method, application to new contexts, or the achievement of innovative results. Ensure that your article clearly outlines the new contribution of your work.
Avoid presenting incremental results that do not significantly contribute to existing knowledge.
1. https://www.mdpi.com/2076-3417/10/23/8382
Author Response
Dear Editors and Reviewers:
We would like to express our sincere thanks for your constructive and positive comments on our manuscript. We have studied comments carefully and have made correction which we hope meet with approval. Revised portions are marked in red for easy tracking. The main corrections in the paper and the responds to the reviewer’s comments are as following:
Reviewer #3
Thank you for your careful review and comments in the manuscript. Firstly, thank you for your recognition of our research. In view of the language problem that you pointed out, we have checked the writing grammars in detail throughout the article and revised them. Besides, we have provided more discussion in the finish paragraph of the introduction to enrich the background research. Then, based on the three amendments you suggested, we thought about it carefully and responded and revised them.
Comment.1: It is recommended to expand your literature review. Ensure that you have explored all relevant research and literature in your field. Include related studies, theories, and prior developments that provide the appropriate context for your work.
Response: Thank you for point out this issue. We have checked the manuscript and added more details and references.
Comment.2: If the proposed method and the use of LCOS have already been reported [1], it is essential to clearly highlight what distinguishes your approach. Are you introducing improvements, modifications, or unique applications? Ensure that your article emphasizes these distinctive aspects. 1. https://www.mdpi.com/2076-3417/10/23/8382
Response: Thank you for your kind suggestion. The report reference is our prior research, which presented the experiment effect of using focused light array generated by SLM to align the optical path. It is one part of the preliminary work of this research. The research work needs more Mathematical models, optical tracing to get the measurement phase map, which is not reported in the reference. Our proposed manuscript is to propose a simple structure of optical path at oblique incidence to get the wavefront and surface information of optical lens and find a solution for the phase diagram calculation method both for measurement and alignment.
Comment.3: If you are using images that have been previously published, make sure to obtain the necessary permissions for their use and properly cite the original sources.
Response: Thank you for your comment. Figure 2 is sourced from our prior research, which is published in an open access journal "Applied Sciences" of MDPI, and we have been informed that we do not need a copyright permission if we want to reuse the Figure from Monja Milicevic(monja.milicevic@mdpi.com), who is the Assistant Editor of "Applied Sciences" of MDPI.
Comment.4: For your work to be considered for publication, you must present a significant new contribution to the field. This may involve enhancements to the existing method, application to new contexts, or the achievement of innovative results. Ensure that your article clearly outlines the new contribution of your work. Avoid presenting incremental results that do not significantly contribute to existing knowledge.
Response: Thank you for your kind advice. We have adjusted the description of the method in our article to better explain its novelty and effect. These revised sentences have been marked in red.
We tried our best to improve the manuscript and made some changes in the manuscript. These changes will not influence the main content and framework of the paper and be marked in red in revised paper.
We appreciate for Editors and Reviewers’ warm work earnestly, and hope that the correction will meet with approval.
Once again, thank you very much for your comments and suggestions.
Best regards,
Corresponding authors:
Zhen Zeng, zengzhen@hbut.edu.cn
Round 2
Reviewer 3 Report
Comments and Suggestions for AuthorsI wish to draw your attention to the fact that the article currently under review exhibits significant resemblances to a work previously published by the same publisher in [1].
This likeness becomes notably apparent in the utilization of identical images within both articles.
The fundamental method and system proposed remain essentially unchanged, with only limited adjustments in processing and application.
1. https://www.mdpi.com/2076-3417/10/23/8382
Author Response
Dear Editors and Reviewers:
We would like to express our sincere thanks for your constructive comments on our manuscript. We have discussed these comments carefully and have made corrections which we hope meet with approval. Revised portions are marked in red for easy tracking.
Reviewer #3
Thank you for your sincere comments in the manuscript. Based on your suggestions, we thought carefully and revised related part of the manuscript.
Comment.1: This likeness becomes notably apparent in the utilization of identical images within both articles.
Response: Thank you for point out this problem. We have redrawn the figures used in the paragraph to illustrate the measurement steps of optical surfaces at oblique incidence.
Comment.2: The fundamental method and system proposed remain essentially unchanged, with only limited adjustments in processing and application
- https://www.mdpi.com/2076-3417/10/23/8382
Response: Thank you for your kind suggestion. We are sorry that this issue makes you confused about the main topic of the manuscript. We have changed the title to “Oblique incidence interferometric measurement of optical sur-face based on a liquid crystal on silicon spatial light modulator”. The point of the study is to present the off-axis parboiled mathematical models and optical tracing to get the measurement phase map, which is not reported in our prior paper. Most importantly, we want to find a solution for the measurement phase calculation method in such oblique incidence interferometric optical setup.
Our prior paper presented the experiment effect of using focused light array generated by SLM to align the optical path. The alignment method could be used in optical system adjustment. And we used it before measuring optical surface, which make the optical element such as the SLM and interferometer at right position and angles.
We have rewrite relevant headings and paragraphs in the introduction and section 2. We hope that these explanations and changes will clear up your confusion.
We appreciate for Editors and Reviewers’ warm work earnestly, and hope that the correction will meet with approval.
Once again, thank you very much for your comments and suggestions.
Best regards,
Corresponding authors:
Zhen Zeng, zengzhen@hbut.edu.cn
