Infusion systems are widely used in clinical medicine. Intravenous infusion therapy must be monitored to ensure patient safety. We proposed a compact flow rate sensor device based on the time-of-flight method. This device included one ceramic heater and two infrared sensors. Practical sensor prototypes were fabricated and characterized. The response time was 30 s. The sensor range was estimated to be 33 dB from μL/min to tens of mL/min, covering almost the entire usage range This flow rate sensor can be applied to common infusion tubes. Through the use of a mobile phone app, detailed information can be presented in real time.

We proposed a single metalens for fiber coupling within telecom bands. This proposed fiber coupler combined a single layer metalens and a Polydimethylsiloxane (PDMS) layer. Instead of traditional fiber collimators, which are bulky and require complex calibration processes, we used a metalens for the focusing of incident and outgoing lasers and achieve achromatic aberration over a certain wavelength band. The focal length was kept as 514.9 μm with a 6.92-μm tolerance. The average coupling efficiency of an achromatic lens was calculated as 0.43. The different phases were produced with the nanopillar element structures. The aim is to provide an idea for creating a more convenient, integrated and efficient way of coupling fiber optics. This approach can also be applied to the design of achromatic lenses in other wavelength regions.

In this paper, a new method for manufacturing flexible and repeatable sensors made of silicon solar cells is reported. The method involves depositing the noble metal film directly onto the Si template and stripping out the substrate with a pyramid morphology by using an adhesive polymer. In order to evaluate the enhancement ability of the substrate, Rhodamine 6G (R6G) were used as surface-enhanced Raman scattering (SERS) probe molecules, and the results showed a high sensitivity and stability. The limit of detection was down to 10⁻¹² M for R6G. The finite-difference time domain (FDTD) was used to reflect the distribution of the electromagnetic field, and the electric field was greatly enhanced on the surface of the inverted pyramidal substrate, especially in pits. The mechanism of Raman enhancement of two types of pyramidal SERS substrate, before and after stripping of the noble metal film, is discussed. By detecting low concentrations of plasmid DNA, the identification of seven characteristic peaks was successfully realized using a noble metallic pyramidal substrate.

We applied multimodal nonlinear optical microscopy and Raman Spectroscopy to rapidly image Oral Squamous Cell Carcinoma (OSCC), comparing results with Hematoxylin-Eosin (H&E) stained to explore supplementary diagnostic methods. With ethical approval and patient informed consent, we processed primary tumor resection tissues, preparing frozen sections. Slice 1 was stained with H&E-stained, while Slice 2 was unstained and imaged using Coherent anti-Stokes Raman Scattering (CARS), Second-Harmonic Generation (SHG), Differential Interference Contrast (DIC), and Raman spectroscopy. These were analyzed alongside H&E-stained sections to assess diagnostic capabilities. Raman spectroscopy revealed distinct differences at 646, 798, 1006, 1091, 1157, 1190, 1450, 1520, and 1660 cm^-1. CARS imaging showed unique cancer nest structures, and SHG highlighted collagen fiber distribution. Multimodal nonlinear imaging, combining CARS, SHG, and DIC, shows potential as a supplementary diagnostic tool for oral squamous cell carcinoma, aiding in the characterization of pathological features and providing valuable clinical diagnostic information.