Materials 2026 • UNT • Optical Sensing

DiscSPR

DiscSPR explores how optical discs can be used as low-cost grating substrates for surface plasmon resonance sensing, with a focus on clear results, practical design, and strong visual presentation.

Explore Method View Results

3 disc types BD-R, DVD-R, and CD-R substrates tested

2 lighting modes Front-side and back-side setups compared

394 nm/RIU Highest measured sensitivity

Featured View

Main sensor image

Use your best setup photo, coated disc image, microscopy image, or project graphic here.

Main finding

Ag + front-side

Silver-coated gratings with front-side illumination gave the clearest and most consistent resonances.

Close-up of the optical disc grating surface

Experimental setup or coated substrate image

Platform Optical disc gratings

Best metal Silver coating

Best setup Front-side illumination

Top sensitivity 394 nm/RIU

Overview

What this project does

This study uses commercial optical discs as low-cost grating substrates for grating-coupled surface plasmon resonance sensing. Instead of using expensive nanofabrication, it takes advantage of the nanostructures already built into the discs and compares how metal coating, disc type, and illumination direction affect performance.

Main conclusion Silver-coated gratings with front-side illumination gave the clearest resonance signals.

Performance insight CD-R showed the biggest refractive index shift, while BD-R gave the sharpest spectral features.

Why it matters This approach lowers cost and makes plasmonic sensing platforms more accessible.

Method

The workflow is organized into four stages. Each image can open a cleaning or preparation video so the process is easier to follow.

Step 01

Disc Preparation

Cut, clean, and isolate the polymer grating substrate.

Step 02

Metal Deposition

Apply Ag or Cu to form the plasmonic layer.

Step 03

Characterization

Measure grating geometry and surface morphology with AFM.

Step 04

Optical Testing

Collect reflectivity spectra and compare with simulation.

Figures

Use this section for your best schematics, AFM images, setup diagrams, and representative spectra.

Sensor Concept

Front-side and back-side plasmon excitation on metal-coated optical disc gratings.

Experimental Setup

Optical path, angle control, polarization handling, and reflectivity collection system.

Morphology & Spectra

AFM-derived geometry and representative resonance behavior across substrates.

Results

The results section highlights the main findings in a simpler format with stronger visual balance.

Highlights

What stood out most

BD-R produced the sharpest resonances. Front-side illumination was more reproducible. Silver outperformed copper. CD-R showed the highest wavelength sensitivity even though its resonance features were broader.

Best resonance: BD-R

Best illumination: Front-side

Best metal: Ag

Highest sensitivity: CD-R

Spectral plot or experimental results image

Sensitivity Summary

Substrate	Sensitivity	Summary
CD-R	394 nm/RIU	Highest wavelength shift
BD-R	321 nm/RIU	Best balance of clarity and consistency
DVD-R	290 nm/RIU	Lowest sensitivity

Impact

This project shows how common commercial materials can be turned into practical sensing platforms at lower cost.

Why it matters

More accessible plasmonic sensing

Commercial optical discs can become functional plasmonic sensing substrates, reducing fabrication barriers for research, teaching, and future diagnostic use.

Next steps

Portable and integrated testing

Future work can add microfluidics, protective coatings, and target-specific sensing chemistry for environmental or biomedical applications.