Phone：+86 431 89825768
E-mail:sales@worldhawk.com
Achromatic optical lenses
Today, we present a checklist to help you understand achromatic optical metalenses, hoping it will be useful for those interested in learning about the topic.
1. Compared with traditional geometric lenses, optical metalenses not only offer superior optical performance but also feature small size and high integrability. They hold broad application prospects in future portable and miniaturized devices, such as augmented reality glasses and smartphone lenses.
2. For traditional geometric lenses, the wavefront is generally reshaped by changing the lens's geometric shape. The chromatic aberration in imaging mainly stems from the material dispersion of the lens.
3. In an optical system composed of traditional geometric lenses, two or three single lenses can be cascaded to compensate for positive and negative dispersion, thereby eliminating chromatic aberration. However, this approach complicates the imaging system and makes it difficult to reduce its size. For metalenses, light of different wavelengths accumulates different phases when passing through a single meta-atom. Moreover, the phase surfaces formed by the outgoing light of different wavelengths are generally different, causing the light to focus at different spatial positions and resulting in chromatic aberration.
4. Researchers have made significant efforts to eliminate the imaging chromatic aberration of metalenses. In principle, micro-nano meta-atoms with controllable phase changes provide a new mechanism for chromatic aberration control. To achieve focusing, it is only necessary to ensure that the phase changes at different positions of the lens, when light passes through, satisfy the following relationship:
Among them, x and y represent the spatial coordinates relative to the center of the lens, (the content originally marked as "picture" is assumed to be "focal length" here) denotes the focal length, and (the content originally marked as "picture" is assumed to be "phase at the corresponding coordinate" here) represents the phase at the corresponding coordinate. Since the phase change of meta-atoms is wavelength-dependent, to achieve achromatic focusing, it is necessary to ensure that the phase at each spatial coordinate can be controlled independently.
5. However, for a single meta-atom, although it is relatively easy to generate the ideal phase for a specific wavelength by changing its geometric dimensions, it is highly challenging to simultaneously generate the phases required for other wavelengths when the wavelength changes.
6. Overall, this is a multi-objective optimization problem that requires sufficient structural degrees of freedom. This also places new demands on the design of meta-atoms. Currently, research on achromatic metalenses is mainly divided into two categories: wavelength-discrete achromatic metalenses and continuous-bandwidth achromatic metalenses.
7. There are numerous optical lens products available on the market. If you are unsure how to select high-quality products, you can try the optical lens products from Wave Optics.
NAVIGATION
CONTACT US
Changchun Worldhawk Optics Co., Ltd.
NO.6116, Ji-Lin Road, Changchun, JiLin,China
MESSAGES
We will contact you within one working day. Please pay attention to your email.