NON-INVASIVE GRADING TECHNIQUE FOR RUBY GEMSTONE USING CHARGE-COUPLED DEVICE (CCD)
At a Glance
Section titled âAt a Glanceâ| Metadata | Details |
|---|---|
| Publication Date | 2023-02-28 |
| Journal | ASEAN Engineering Journal |
| Authors | Fatinah Mohd Rahalim, Juliza Jamaludin, Syarfa Najihah Raisin |
| Institutions | Universiti Sains Islam Malaysia |
| Citations | 1 |
| Analysis | Full AI Review Included |
Technical Documentation & Analysis: Non-Invasive Gemstone Grading via CCD
Section titled âTechnical Documentation & Analysis: Non-Invasive Gemstone Grading via CCDâExecutive Summary
Section titled âExecutive SummaryâThis research validates a non-invasive, quantitative method for grading ruby clarity based on light intensity distribution using a Charge-Coupled Device (CCD) linear sensor system. This application highlights the critical role of highly stable, transparent materials in advanced optical sensing.
- Core Achievement: Development of a CCD linear sensor system capable of non-invasive clarity grading for gemstones by measuring light attenuation.
- Performance Metric: The system demonstrated a high reliability of 80% accuracy in validating the light distribution characteristics of the ruby.
- Quantitative Output: The system converts light intensity passing through the ruby into a measurable voltage output (Experimental Value: 1.7918 V).
- Material Requirement: The success relies on the high hardness, stable chemical, and superior optical transparency of the gemstone (ruby, Corundum), properties where MPCVD diamond offers significant advantages.
- Methodology: The experiment required strict environmental control (25°C-33°C, 65%-85% RH) and precise optical alignment (0.5 lux laser intensity) in a dark environment.
- 6CCVD Value Proposition: Diamondâs superior optical, thermal, and mechanical stability makes it the ideal material for replicating or enhancing the optical components (windows, protective layers) required for high-precision, standardized grading systems.
Technical Specifications
Section titled âTechnical SpecificationsâThe following hard data points were extracted from the research detailing the system performance and operational requirements:
| Parameter | Value | Unit | Context |
|---|---|---|---|
| System Accuracy | 80 | % | Reliability in detecting light distribution |
| Experimental CCD Output Voltage (Ruby Present) | 1.7918 | V | Measured output under Laser ON condition |
| Theoretical CCD Output Voltage | 1.9941 | V | Calculated via light reflectance and attenuation models |
| Laser ON Reference Voltage (No Ruby) | 1.583 | V | Reference voltage at 1 lux light intensity |
| Laser OFF Reference Voltage (No Ruby) | 4.282 | V | Reference voltage at 0 lux light intensity |
| Optimum Operating Temperature Range | 25 - 33 | °C | Required for CCD linear sensor efficiency |
| Optimum Relative Humidity Range | 65 - 85 | % | Required for CCD linear sensor efficiency |
| Incident Light Intensity (Laser) | 0.5 | lux | Maintained for optimum CCD linear sensor working conditions |
| CCD Voltage Output vs. Light Intensity Gradient | -2.6983 | V/lx | Inverse proportionality relationship |
Key Methodologies
Section titled âKey MethodologiesâThe non-invasive grading system relies on precise environmental control and optical alignment to ensure the CCD linear sensor operates optimally without saturation.
- Environmental Setup: The experiment was conducted in a dark area to ensure the CCD received the highest possible light intensity from the laser source, minimizing external light noise.
- Condition Control: Strict maintenance of the operating environment was required: Temperature (25°C-33°C) and Relative Humidity (65%-85%).
- Optical Alignment: A low-power laser (0.5 lux) was beamed towards the CCD linear sensor, with the ruby placed in the optical path to measure light attenuation.
- Sensing Mechanism: The CCD linear sensor analyzed the light intensity passing through the ruby and converted this optical input into a voltage value.
- Data Acquisition: An Arduino Uno Microcontroller was used to manage the system, with the final voltage output displayed on an oscilloscope.
- Modeling and Analysis: Light propagation characteristics (reflection and attenuation, based on Beer-Lambert Law) were mathematically modeled using LabVIEW, and statistical validation (2-sample t-test) was performed using Minitab.
6CCVD Solutions & Capabilities
Section titled â6CCVD Solutions & CapabilitiesâThe research successfully demonstrates a high-precision optical sensing application that requires materials exhibiting exceptional transparency, hardness, and thermal stabilityâcharacteristics inherent to MPCVD diamond. 6CCVD is uniquely positioned to supply the advanced diamond components necessary to industrialize or extend this technology.
Applicable Materials
Section titled âApplicable MaterialsâThe paper explicitly notes that ruby is valued for its high hardness (9 on Mohs scale), strong chemical/thermal stability, and optical transparency. Single Crystal Diamond (SCD) surpasses ruby in every one of these critical properties, making it the ideal choice for high-reliability optical systems.
| Application Requirement | 6CCVD Material Recommendation | Key Advantage |
|---|---|---|
| High Optical Transparency (UV to IR) | Optical Grade SCD | SCD offers the widest transmission range and lowest absorption coefficient, crucial for precise light attenuation measurements. |
| Extreme Hardness & Durability | Optical Grade SCD | Mohs hardness 10. Ideal for protective windows or sensor covers in industrial environments where abrasion or damage is a concern. |
| Thermal Stability (High Power Laser Use) | High Purity SCD | Diamond possesses the highest known thermal conductivity, ensuring sensor stability and preventing thermal drift under laser irradiation. |
| Sensor Integration/Electrodes | Boron-Doped Diamond (BDD) | If the system requires integrated electrochemical sensing or highly stable, conductive electrodes, BDD provides superior performance. |
Customization Potential
Section titled âCustomization Potentialâ6CCVDâs advanced manufacturing capabilities directly address the need for precision components in optical systems like the one described:
- Custom Dimensions: We provide SCD and PCD plates/wafers in custom sizes, including large-area PCD wafers up to 125mm for large-format optical windows or sensor arrays.
- Ultra-Low Roughness Polishing: For critical optical applications requiring minimal light scattering, 6CCVD guarantees Ra < 1nm for SCD and Ra < 5nm for inch-size PCD. This ensures maximum light transmission efficiency and accuracy in attenuation measurements.
- Integrated Metalization: If the CCD sensor or optical components require integrated contacts or reflective layers, 6CCVD offers in-house metalization services, including Au, Pt, Pd, Ti, W, and Cu deposition.
Engineering Support
Section titled âEngineering SupportâThe successful implementation of this non-invasive grading technique requires deep expertise in material science and optical physics.
- Optical Path Optimization: 6CCVDâs in-house PhD team specializes in optimizing diamond material properties (e.g., thickness, nitrogen concentration, surface finish) to maximize light transmission and minimize reflection losses for specific wavelengths (as modeled by the paperâs light reflectance equation).
- Sensor Integration: We provide consultation on integrating diamond optical windows or protective layers directly onto CCD or CMOS sensors, ensuring thermal stability and long-term operational reliability for similar Non-Invasive Optical Sensing projects.
- Global Supply Chain: We offer global shipping (DDU default, DDP available) to ensure rapid delivery of custom diamond materials worldwide.
For custom specifications or material consultation, visit 6ccvd.com or contact our engineering team directly.
View Original Abstract
Ruby is one of the most popular and high-value gemstones that always attract the gemologist and jeweler in the diamond market. The wide use of ruby in various industries makes the grading of this gems more complicated due to a lot of synthetic and imitation rubies are made. The current grading techniques are mostly depending on the human visual assessment which prone to errors. This paper proposes a system that helps in grading the clarity characteristic of the ruby in non-invasive manner. The system includes a charge-coupled devices (CCD) and laser that is designed in the most suitable and effective way to conduct inspection on the light intensity of the ruby which will then determine the clarity of the ruby. CCD linear sensor is widely known as the reliable sensor especially when use in the optical system. The CCD linear sensor capture the light intensity from the ruby and convert it into the voltage value. The result shows a value of 1.7918 V obtained from the CCD linear sensor when ruby is placed in the system. This concludes that the CCD system can detect even slightest changes in the light intensity that can pass through the ruby and falls on the CCD linear sensor. The system is proven to be a reliable and effective system with 80% accuracy.