Aspheric lenses reduce aberration and provide sharper images with improved spot size compared to spherical lenses. This paper demonstrates that applying shear flow can produce plano‐concave liquid crystal (LC) lens arrays with paraboloid aspheric profiles. The focal length of individual lenses, with a 0.2 mm aperture, decreases from 0.67 to 0.45 mm as the chiral dopant increases from 0 to 6 wt%. The focal length is also sensitive to the polarization state of the incoming light. The lenses are stabilized by photopolymerizing with 6 wt% of reactive monomer added to the LC. A qualitative explanation for the flow‐induced lens formation and the optical properties of the lenses is provided. The potential tunability of the lenses in various fields and their use as paraboloid reflectors are discussed.
The majority of optical lenses have spherical surface profiles because they are convenient to fabricate. Replacing spherical optics with aspheric optics leads to smaller size, lighter weight, and less complicated optical systems with a superior imaging quality. However, fabrication of aspheric lenses is expensive and time-consuming. Here, we introduce a straightforward and low-cost casting method to fabricate polymeric aspheric lenses. An elastomeric ferrogel was formed into an aspherical profile by using a designed magnetic field and then was used as a mold. Different types of aspherical profiles from parabola to hyperbola can be formed with this method by tuning the magnetic field. A home-built Shack–Hartmann sensor was employed to characterize the cast polymeric lenses. The effects of magnetic field intensity, gradient of the magnetic field, and magnetic susceptibility of the ferrogel on the lens profiles were investigated. This technique can be used for rapid-forming polymeric aspherical lenses with different sizes and shapes.
more » « less- NSF-PAR ID:
- 10138146
- Publisher / Repository:
- Optical Society of America
- Date Published:
- Journal Name:
- Applied Optics
- Volume:
- 59
- Issue:
- 8
- ISSN:
- 1559-128X; APOPAI
- Format(s):
- Medium: X Size: Article No. 2632
- Size(s):
- Article No. 2632
- Sponsoring Org:
- National Science Foundation
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