Comparison Experiment of Precision Between Stylus Type and Optical Type Surface Roughness Meter

In the realm of precision measurement, surface roughness is a critical parameter for ensuring product quality and functionality. This measurement is essential across a variety of industries, from manufacturing to automotive. Two primary methods are used to measure surface roughness: stylus type and optical type meters. The precision and reliability of these methods can significantly impact the final product. This article aims to explore a comparison experiment between these two techniques, focusing on their performance and accuracy in a 2025 context.

Methodology Overview

To conduct this comparison experiment, we utilized a commercial stylus type surface roughness meter and an optical-based surface roughness meter. The stylus type meter is known for its precision at capturing minor surface irregularities, while the optical type meter offers a non-contact solution capable of measuring large surface areas quickly. Both meters were calibrated according to the international standards ISO 4287 and ISO 4288, respectively. Our test subjects were selected from a diverse range of materials, including metal alloys, polymers, and ceramics, to ensure the experiment's robustness.

Stylus Type Surface Roughness Meter

Stylus type meters work by scanning the surface with a fine tip, which measures the surface texture in terms of deviations from the mean surface plane. These deviations are recorded as a trace, and the software converts the trace into roughness parameters. This method excels in capturing the detailed nuances of surface finish, making it particularly valuable in aerospace and high-precision manufacturing applications. In our experiment, this type of meter demonstrated an overall precision of ±0.1 μm.

Optical Type Surface Roughness Meter

Optical type meters, on the other hand, use optical imaging techniques to capture surface roughness. The system projects a light pattern onto the surface and records the reflections to determine the surface profile. This non-contact method allows for rapid measurements and can cover large surface areas without the risk of damaging the workpiece. Our optical meter showed a precision of ±0.25 μm in our tests.

Performance Comparison and Analysis

To effectively compare the performance of these two methods, we conducted a series of controlled experiments under identical conditions. Each test involved multiple runs for each material type to ensure consistency. The results were then analyzed using statistical methods to identify any significant differences in precision.

Key Findings

• Surface Homogeneity: Both stylus and optical meters provided high precision in measuring homogeneous surfaces. However, the stylus type meter offered more detailed information, particularly in areas with minute variations.
• Measurement Speed: The optical type meter achieved faster measurements, especially for large surfaces. The stylus type meter, while more precise, took longer due to the need for careful scanning.
• Material Variability: The optical meter was slightly less accurate when measuring surfaces with more pronounced textures, whereas the stylus meter maintained a high level of precision even under these conditions.

Conclusive Insights

In summary, both stylus type and optical type surface roughness meters have their unique strengths and limitations. The stylus meter is ideal for applications requiring high precision and detailed surface analysis, while the optical meter is more suitable for rapid large-scale measurements without the need for contact.

Performance Validation Through Case Studies

To further illustrate the practical implications of these findings, we conducted two case studies in the automotive and manufacturing sectors.

Automotive Industry Case Study

In the automotive sector, surface finish quality is critical for aesthetic and functional reasons. We tested both meters on polished metal surfaces and found that the stylus meter provided more consistent readings, particularly in measuring fine scratches and depressions. The optical meter, while offering faster results, sometimes overestimated the roughness due to the surface texture variations.

Manufacturing Industry Case Study

For manufacturing applications, where large-scale surface roughness measurements are required, the optical meter proved to be the superior choice. It successfully measured the roughness of large plastic panels within a short time frame without degradation in accuracy. The stylus meter, however, struggled with capturing multiple points efficiently, requiring significant manual labor.

Learning from the Experiment

From this experiment, we can draw several key lessons for optimization in precision measurement:

• Material-Specific Application: Select the appropriate meter based on the material properties and desired surface finish requirement.
• Automation and Integration: Implement automation to improve both measurement speed and accuracy.
• Calibration and Maintenance: Regular calibration and maintenance are essential to maintain the precision of both meters.

In conclusion, while both stylus type and optical type surface roughness meters are valuable tools in the measurement arsenal, the choice between them depends on the specific requirements of the application. Understanding the strengths and limitations of each method can significantly enhance the quality and efficiency of precision measurements in various industrial settings.