Choosing the Right Aspheric Shape for Lens Design Using SYNOPSYS

When designing lenses, the choice of aspheric shape is critical for achieving the desired performance characteristics. This article provides a comprehensive guide on how to select the most appropriate aspheric shape using the SYNOPSYS lens design program. By leveraging the Automatic G-Variables Test (AGT), designers can effectively determine the best G-terms to use on each lens surface.

Understanding Aspheric Shapes in Lens Design

Aspheric surfaces, as opposed to parabolic or spherical surfaces, offer unique optical performance benefits. They can correct for spherical aberrations and provide greater optical clarity and resolution. However, selecting the right aspheric shape requires a detailed understanding of the lens design requirements and limitations.

Introduction to G-Terms and Their Role

In the context of aspheric surfaces, G-Terms refer to a set of coefficients used to express the shape of the surface. These coefficients define the deviation from a standard spherical surface and can be manipulated to achieve specific optical effects. The number and type of G-Terms depend on the complexity of the aspheric shape being considered.

The Role of AGT in Aspheric Surface Design

AGT (Automatic G-Variables Test) is a powerful tool within the SYNOPSYS software. It simplifies the process of determining which G-Terms are most effective on a given lens surface. AGT performs a series of automated tests to evaluate different combinations of G-Terms and select the ones that yield the best performance.

Steps to Use AGT:

Input the required lens design parameters into SYNOPSYS.

Select the AGT option to begin the automated G-Variables test.

Analyze the results to identify the most effective G-Terms for the specific surface under consideration.

Refine the G-Terms to optimize the overall lens performance.

Practical Examples of Aspheric Surface Design

To illustrate the application of AGT in aspheric surface design, consider a high-precision camera lens. By using AGT, designers can accurately determine the most effective G-Terms for each surface, leading to improved resolution and reduced spherical aberrations.

Another example is a projection lens for cinema screens. Here, AGT helps in optimizing the G-Terms to ensure uniform illumination and minimal distortion across the screen. This results in a more vibrant and immersive viewing experience for the audience.

Best Practices and Considerations

While AGT is a powerful tool, it is essential to consider other factors when selecting aspheric shapes. These factors include:

System requirements and constraints

Material characteristics and manufacturing limitations

Expected performance under different conditions (e.g., different wavelengths, environmental factors)

By integrating ASGT with these considerations, designers can achieve optimal aspheric lens design results.

Conclusion

Selecting the right aspheric shape is crucial for achieving the best optical performance in lens design. By utilizing AGT in the SYNOPSYS program, designers can accurately determine the most effective G-Terms for each surface. This process, combined with a thorough understanding of aspheric shapes and best practices, ensures that the final lens design meets the highest standards of performance and reliability.

Whether you are working on a high-resolution camera or a projection system, the use of ASGT in SYNOPSYS can significantly enhance your design process, leading to superior optical performance.