Ultra-Sensitive Intensity Modulated Strain Sensor by Tapered Thin-Core Fiber Based Modal Interferometer
Round 1
Reviewer 1 Report
The authors proposed a tapered thin core fiber sensor based on modal interference. The sensor was investigated theoretically by BPM and experimentally studied. The results the sensor is very promising for high precision strain sensing. The logic and presentation of the paper are good. Recommend to accept.
Author Response
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Author Response.pdf
Reviewer 2 Report
Dear Colleagues!
After reading your article, I came to the conclusion that it was methodologically well written, contains clearly structured sections, and could be published.
But suddenly the question arose, why do you not mention the already known analogues of your interferometer or very close to it in the set of articles that you refer to ???
For example, I didn't find following articles in your references "Ultrahigh sensitivity with different taper geometries of thin-core fiber modal interferometer for refractive index sensing", "Tapered Thin Core Fiber Based Multi-mode Interferometer for Refractive Index Sensing", "An in-line Mach-Zehnder Interferometer Using Thin- core Fiber for Ammonia Gas Sensing With High Sensitivity ".
From the titles it is clear that the developed sensors are in no way intended to measure strain or deformations, since the thinned fiber is not intended for such deformation loads. Then the question arises, you are measuring almost 1000 microstrains of deformation, how many cycles of operation of your sensor do you expect?
Consequently, the article completely lacks a section related to the solidity of your sensor, its areas of real application and the length of the life cycle.
Besides, probably, the phrase in the annotation about the novelty of your proposal should also be explained. Maybe it is in your previous works? It turns out that it is not either, since you are talking everywhere only about sensitivity and errors. But don't talk about the range of the measuring conversion.
Thus, I can recommend your article for publication, after some revision.
Author Response
Please see the attachment
Author Response File: Author Response.pdf
Reviewer 3 Report
This paper reports an ultra-Sensitive Intensity Modulated Strain Sensor by Tapered Thin-Core Fiber Based Modal Interferometer. I have some comments to be addressed in order to improve the paper technical quality for a broad audience.
- Introduction: it is missing some references about latest impact works on sensing fabrication using polymer fiber sensor, where is quite used for strain sensors due to particular properties of the polymer material. Please consider to add and discuss: Advances on polymer optical fiber gratings using a KrF pulsed laser system operating at 248 nm, Fibers 6 (1), 13, 2018.
- There is a missing about some words regarding potential application of strain sensors for real scenario and applications using not only silica fiber but also polymer materials. Please add some words about it focusing different fields textiles, industry, civil, etc. Recent developments in polymer optical fiber strain sensors: A short review. J Opt 50, 299–313 (2021); Smart textiles for multimodal wearable sensing using highly stretchable multiplexed optical fiber system, Scientific Reports 10 (1), 1-12, 2020; Highly stretchable hybrid silica/polymer optical fiber sensors for large-strain and high-temperature application," Opt. Express 27, 20107-20116 (2019).
- How about the reproducibility of the sensor proposed (presented method in Fig. 3) comparing with FBG technology? Please add some words.
- How about the repeatability of the sensor performance if different cycles of strain is applied (increasing and decreasing cycles of strain)?
- Why a temperature range so small? why just 25 to 33ºC? For a real application as mentioned in comment 3 it can be a problem.
Author Response
Please see the attachment
Author Response File: Author Response.pdf
Round 2
Reviewer 2 Report
I carefully read the authors' responses to the suggestions and comments of all reviewers. I believe that their clear and methodologically competent article, in which they eliminated a number of remarks, and significantly supplemented some of the sections, has become even more interesting for the reader both from the point of view of scientific significance and completeness of the presented material. I believe that the article can be published.
Reviewer 3 Report
The paper was improved as suggested
