| dc.description.abstract | Traditional non-optical gas detectors are often limited by their susceptibility to interference from other gases, affecting their performance in specific applications. Optical gas detectors, due to their high sensitivity, rapid response, and specificity, have gained attention in the market. However, their high costs have restricted widespread use. To address these issues, this study designs and develops a concentration detection system based on a non-collimated light source. By integrating a non-collimated optical path design into the architecture of the optical concentration detection system, we aim to reduce costs while maintaining high sensitivity and fast response. We plan to use a visible light system and ink solution as a feasibility study sample to evaluate the feasibility and performance of this new design.
We used ASAP ray-tracing software to model the system and the light source, simulating the optical path and measuring the light transmittance of samples with different concentrations. By simplifying system parameters through simulation, mathematical fitting, and slope analysis, we identified the relationship between light intensity and concentration, and explored the system′s working range and limitations. Experimental results show that the system can stably measure sample concentrations in the range of 10-35 ppm, with residuals less than 1 ppm from actual concentrations. These results confirm the feasibility of using non-collimated light sources for concentration detection, and we propose changes needed for real-world gas detection applications as well as suggestions for improving system performance. | en_US |