Custom Collimating Lenses and Collimator Lens Design
A collimating lens converts divergent light into a near-parallel beam, but achieving the required beam performance depends on more than focal length alone. Source geometry, wavelength, numerical aperture, beam diameter, and mechanical integration all influence the final design.
Shanghai Optics designs and manufactures custom collimating lenses for laser, optical testing, spectroscopy, imaging, and illumination systems.
In practical systems, collimation performance depends on the source size, source position, focal length, optical aberrations, and alignment. For extended or highly divergent sources, the collimator should be designed around the actual source geometry and required output divergence.
Collimating Lens Design Considerations
The correct collimator architecture depends on the source and required output beam. A laser diode, fiber source, LED, extended target, or optical test source can impose very different requirements on numerical aperture, aberration correction, focal length, and clear aperture.
Key design parameters typically include:
- Source type and emitting area
- Operating wavelength or spectral range
- Focal length
- Numerical aperture
- Required beam diameter
- Output divergence
- Clear aperture
- Field of view
- Mechanical envelope
Depending on the performance requirements, the design may use spherical, aspheric, achromatic, or multi-element optics.
Custom Collimating Lenses for Laser and Optical Systems
Shanghai Optics develops collimating optics around the source, wavelength, beam requirements, and mechanical constraints of the system. Designs can support laser collimation, beam expansion, interferometry, optical testing, spectroscopy, imaging, and sensor evaluation.
Depending on the application, collimating optics can be designed for wavelengths including 405 nm, 543 nm, 633 nm, 780 nm, 1064 nm, 1310 nm, 1550 nm, and 2000 nm, with optical materials and coatings selected according to system requirements.
Custom Collimator Lens Design
A custom collimator is often required when beam quality, field of view, spectral range, entrance pupil, or mechanical constraints cannot be met with a simple lens configuration.
For optical testing, a collimator may be designed to project a target at optical infinity for evaluating cameras, imaging optics, or other infinite-conjugate systems. In these cases, the design may need to account for entrance pupil diameter, wavelength, focal length, field of view, and required wavefront performance.
Collimating Lens Applications
Collimating lenses are used where beam direction, divergence, or angular distribution must be controlled before light reaches the next optical element or subsystem.
- Laser systems — reduce source divergence and prepare the beam for downstream optics, scanning, processing, or beam expansion.
- Optical testing — project targets or sources at optical infinity for evaluating cameras, imaging lenses, sensors, and other infinite-conjugate systems.
- Spectroscopy — control the light path between the source, sample, dispersive optics, and detector.
- Beam expanders — work with focusing optics to increase or reduce beam diameter while maintaining a near-collimated output.
- Imaging and sensor testing — create controlled illumination or angular conditions for evaluating optical and detector performance.
- Fiber-optic systems — couple light between optical fibers and free-space optical systems. For fiber-specific solutions, see our Fiber Collimators.
From Optical Design to Collimator Assembly
Shanghai Optics supports collimator development from optical design through component manufacturing, coating, mechanical integration, assembly, and testing.
Final system performance can depend on surface figure, surface quality, centration, element spacing, coating performance, housing tolerances, and mechanical alignment. For demanding systems, these factors should be evaluated as part of the complete optical assembly rather than as isolated lens specifications.
Collimating Lens FAQs
Focal length should be selected together with the source size, numerical aperture, and required output beam diameter. For an ideal point source positioned at the focal plane, the emerging rays are theoretically parallel. In practical systems, finite source size, aberrations, alignment, and clear aperture also affect the result. For this reason, focal length alone is usually not enough to specify a collimator for a precision optical system.
Residual divergence depends on the source size, source position, lens focal length, numerical aperture, aberrations, and alignment. A finite source cannot generally produce a perfectly parallel beam, so the design must account for the actual source geometry and required angular performance.
For an ideal thin lens, a point source positioned at the focal plane produces a collimated output. In real optical systems, the optimum source position may vary because of lens thickness, principal-plane location, aberrations, source geometry, and assembly tolerances. Precision systems should therefore be aligned based on measured beam performance rather than relying only on the nominal focal length.
An aspheric lens can be useful when spherical aberration must be reduced while maintaining a compact optical design. It is commonly considered for highly divergent laser diodes and other high-numerical-aperture sources. Whether an asphere is the best choice depends on wavelength, beam quality requirements, packaging, and cost.
An achromatic design is typically preferred when the collimator must operate across multiple wavelengths or a broader spectral band. By reducing chromatic focal shift, achromatic optics can improve performance in spectroscopy, imaging, and broadband illumination systems.
Typical starting parameters include the source type and size, wavelength range, focal length, beam diameter, numerical aperture, divergence, clear aperture, field of view, and mechanical envelope. For optical testing applications, entrance pupil diameter and the characteristics of the system under test may also be important.
Yes. A collimator can place a target or source at the focal plane so the system under test receives a near-collimated beam corresponding to an object at optical infinity. This approach is commonly used for testing cameras, telescopes, imaging lenses, and other infinite-conjugate systems.
A collimating lens is the optical element or lens assembly used to reduce beam divergence. A fiber collimator is a specialized assembly designed specifically around light entering or exiting an optical fiber. Fiber collimators therefore also need to account for the fiber numerical aperture, mode characteristics, alignment, connector interface, and mechanical stability.
Yes. Coating specifications can be selected around the operating wavelength, substrate, angle of incidence, laser power, and required transmission performance. Shanghai Optics can provide coatings for visible, near-infrared, and other wavelength ranges depending on the optical design and application requirements.
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