In the realm of precision optics, few lens configurations offer the balance of performance and versatility of Steinheil triplets . At Ross Optical, these lenses are a cornerstone of our catalog, serving industries that demand high-quality imaging and beam control.
Explore our catalog of Steinheil triplets today!
Steinheil Triplet: An Overview
As a part of the achromat family, Steinheil triplets are compound lenses designed with three elements: one low-index crown element configured between two identical meniscus flint elements. These unique lenses are designed for 1:1 conjugation, performing well for conjugate ratios up to 5.
Key Optical Features:
| Diameter | Dia. Tolerance | CT Tolerance | Centering | Irregularity | Surface Quality | Bevel |
| 6.00-25.00 | +0.00 / -0.10 | ±0.2 | 3-5 minutes | 0.5 Waves | 60-40 | 0.25 x 45° |
| Dimensions | MM | |||||
| Clear Aperture | CA >= 90% of Diameter | |||||
| Coating | 1/4wave MgF2 @ 550nm (See Coating Chart for Available Options) | |||||
| Design Wavelength | 587.6nm | |||||
| Focal Length Tolerance | ±2% | |||||
| Edge Thickness | Reference | |||||
| * All dimensions are in mm | ||||||
This symmetrical configuration provides a degree of self-correction to optimize the aberration control of the lens, typically for finite conjugate ratios. Their ability to minimize spherical and chromatic aberrations makes them a go-to solution for applications requiring high image fidelity in compact spaces.
Want to learn more about how achromats eliminate aberrations? Read the first part of our achromat series, “The Role of Achromats in Reducing Chromatic and Spherical Aberrations,” on our blog today!
Applications for Laser Systems & Relay Optics
In laser-based systems, precision and clarity are critical, especially in applications like beam collimation and shaping, optical metrology, and laser marking and inspections. Steinheil triplets, with their compact design and excellent aberration correction, are particularly well-suited for these roles.
Why Steinheil Triplets Work for Lasers
- Short Focal Lengths: Available in focal lengths as low as 7.5 mm, Steinheil triplets enable tight beam control and compact optical layouts.
- Aberration Correction: Their symmetrical design minimizes spherical and chromatic aberrations, ensuring clean beam profiles and accurate targeting.
- High Transmission Coatings: With laser damage threshold (LDT) coatings, lenses support high transmission and low reflection.
Their coatings and material composition make them suitable for visible and near-IR wavelengths. And their symmetrical design ensures consistent performance even in both on- and off-axis applications, which is a critical feature for complex beam paths in industrial and research environments
Manufacturing Challenges
While Steinheil triplets offer exceptional optical performance, their production and procurement involve several technical and logistical hurdles. Ross has developed specialized capabilities to overcome these challenges and deliver consistent, high-quality components to OEMs across industries.
Material Selection
The performance of a Steinheil triplet hinges on the precise pairing of crown and flint glass. These materials must be carefully selected to balance refractive indices and dispersion properties, ensuring optimal correction of spherical and chromatic aberrations.
Precision Fabrication
The triplet’s three-element design requires precise alignment during cementing, as well as tight surface quality control, because they often have steep radii. Even minor deviations can introduce optical aberrations or reduce system efficiency. Ross facilities in El Paso, TX, and Gardner, MA, are equipped with advanced metrology tools and skilled technicians to meet these demanding tolerances.
Coatings: A Critical Performance Layer
Optical coatings are essential to the performance of Steinheil triplets, especially in laser-based systems. We offer ¼ wave MgF₂ coatings at 550 nm as standard, but also provide custom coatings tailored to specific wavelengths and environmental conditions.
Ross delivers LDT coatings, which are engineered to withstand high-power laser exposure without degrading. By integrating LDT coatings into Steinheil triplets, we ensure that the lenses not only perform optically but also endure the thermal and photonic stresses of high-energy environments.
Ross provides laser damage resistance testing to ensure achromatic lenses meet quality standards. Explore how our optical inspection capabilities can be customized to your needs.
Sample Test Highlight:
A recent test was performed on an achromatic lens coating at 1550 nm wavelength, using a 0.5 Hz pulse repetition frequency and 60 ns pulse width. The coating was exposed to a peak power density of 6000 W/cm² across 10 sites, with 100 shots per site.
Result: No damage was observed under 100x Nomarski brightfield microscopy, confirming the lens meets stringent quality standards.
Steinheil triplets exemplify the balance between optical precision and mechanical simplicity. Their ability to correct aberrations, support compact designs, and maintain clarity across on- and off-axis applications makes them indispensable in modern optics.
At Ross, we understand that performance is only part of the equation. That’s why we complement our Steinheil triplet offerings with LDT coatings, custom engineering support, and supply chain solutions that help OEMs overcome sourcing and manufacturing challenges.
Partner with our team of experts to find the perfect optical solution for your project. Contact us today.
