Optimizing optical paths and controlling scattering remain significant challenges in the design of high-performance optical systems for both research and industrial applications. A key component that dramatically enhances system efficiency is the Freeform Surface Mirror (also known as an Off-Axis Parabolic Mirror), offering particular value for academic research, terahertz laser systems, and semiconductor laser applications.
To enable the production of precision-molded aspheric components, we have integrated the Moore 250 UPL V3 ultra-precision diamond turning lathe and plan to introduce the Moore 650. Ahead of reaching full production capacity, we have commenced custom machining of Off-Axis Parabolic Mirrors (including Freeform Surface Mirrors / Freeform Integrating Mirrors) for select clients, delivering reliable solutions for advanced optical systems.
Introduction to Off-Axis Parabolic Mirrors
An Off-Axis Parabolic Mirror features a reflective surface that is a segment of a paraboloid, with its focal point located off the optical axis. Incident light parallel to the mirror’s central axis is reflected and precisely converged at this focal point, enabling exceptional beam control.
Key Features:
- High reflectivity with minimal scatter
- Broad spectral compatibility from UV to IR
- Ideal for laser focusing, terahertz systems, and reflective optics
Functional Principle: In an optical layout, an off-axis parabolic mirror can precisely focus collimated light to a point while avoiding beam path obstruction and eliminating the complexity of aligning multiple optical elements.
Hobbite offers standard specifications with diameters of 12.7 mm, 25.4 mm, 50.8 mm, and 76.2 mm. Coatings include Gold, Silver, and Aluminum, with a standard 90° off-axis angle. These mirrors meet the demands of visible, near-infrared, and infrared applications and are widely used in reflective optical systems, laser focusing assemblies, and terahertz systems.
Characteristics of Freeform Surface Mirrors
Feature | Description |
Surface Type | Asymmetric, high-reflectivity curved surface |
Optical Path Optimization | Optimizes layout to enhance overall system efficiency |
Fabrication Method | Complex surface formed monolithically, replacing multi-element groups and simplifying alignment |
Spectral Range | UV – IR |
Coatings | Gold / Silver / Aluminum |
Primary Applications | Laser focusing, Reflective optics, and Terahertz systems |
Freeform Integrating Mirror Manufacturing Specifications
Parameter | Specification |
Material | Oxygen-Free Copper / Aluminum Alloy |
Processing Size Range | 1 – 400 mm |
Diameter Tolerance | ±0.03 mm |
Surface Finish (US Standard) | 60-40 or 40-20 |
Surface Accuracy | λ/10 @632.8 nm or better |
Laser Damage Threshold | >5 J/cm², 20 ns, 20 Hz @1064 nm |
Clear Aperture | >90% |
Reflectivity | >99.5% or higher |
Standard Off-Axis Parabolic Mirror Dimensions
Aperture | Focal Length | Off-Axis Angle |
0.5 in (12.7mm) Hole-free
| 0.5 in / 12.7mm | 90° |
1 in / 25.4mm | 90° | |
1.5 in / 38.1mm | 90° | |
2 in / 50.8mm | 90° | |
3 in / 76.2mm | 90° | |
4 in / 101.6mm | 90° | |
5 in / 127mm | 90° | |
0.5 in (12.7mm) Holed
| 0.5 in / 12.7mm | 90° |
1 in / 25.4mm | 90° | |
1.5 in / 38.1mm | 90° | |
2 in / 50.8mm | 90° | |
3 in / 76.2mm | 90° | |
4 in / 101.6mm | 90° | |
5 in / 127mm | 90° | |
1 in (25.4mm) Hole-free
| 1 in / 25.4mm | 90° |
1.5 in / 38.1mm | 90° | |
2 in / 50.8mm | 90° | |
3 in / 76.2mm | 90° | |
4 in / 101.6mm | 90° | |
5 in / 127mm | 90° | |
6 in / 152.4mm | 90° | |
7 in / 177.8mm | 90° | |
8 in / 203.2mm | 90° | |
1 in (25.4mm) Holed
| 1 in / 25.4mm | 90° |
1.5 in / 38.1mm | 90° | |
2 in / 50.8mm | 90° | |
3 in / 76.2mm | 90° | |
4 in / 101.6mm | 90° | |
5 in / 127mm | 90° | |
6 in / 152.4mm | 90° | |
7 in / 177.8mm | 90° | |
8 in / 203.2mm | 90° | |
2 in (50.8mm) Hole-free
| 2 in / 50.8mm | 90° |
3 in / 76.2mm | 90° | |
4 in / 101.6mm | 90° | |
5 in / 127mm | 90° | |
6 in / 152.4mm | 90° | |
7 in / 177.8mm | 90° | |
8 in / 203.2mm | 90° | |
2 in (50.8mm) Holed
| 2 in / 50.8mm | 90° |
3 in / 76.2mm | 90° | |
4 in / 101.6mm | 90° | |
5 in / 127mm | 90° | |
6 in / 152.4mm | 90° | |
7 in / 177.8mm | 90° | |
8 in / 203.2mm | 90° | |
3 in (76.2mm) Hole-free
| 3 in / 76.2mm | 90° |
4 in / 101.6mm | 90° | |
5 in / 127mm | 90° | |
6 in / 152.4mm | 90° | |
7 in / 177.8mm | 90° | |
8 in / 203.2mm | 90° | |
3 in (76.2mm) Holed
| 3 in / 76.2mm | 90° |
4 in / 101.6mm | 90° | |
5 in / 127mm | 90° | |
6 in / 152.4mm | 90° | |
7 in / 177.8mm | 90° | |
8 in / 203.2mm | 90° |
Note: Custom machining is available for larger apertures upon request.
Why Choose Freeform Surface Mirrors?
- Simplified Assembly: Monolithic complex surfaces replace multi-element groups, reducing alignment errors and complexity.
- Superior Optical Performance: High reflectivity and low scattering enhance beam quality and overall system efficiency.
- Broadband Compatibility: Usable from UV to IR, suitable for high-precision systems like lasers and terahertz setups.
- Customization: Available in custom apertures and coatings to meet diverse research and industrial needs.
If your optical system demands high precision, maximum efficiency, and simplified alignment, Freeform Surface Mirrors are a powerful solution worth serious consideration.
