Ms. Lingshan Li Profile

Lingshan Li

Senior Optical Engineer

SPIE Involvement:

Author

Publications (2)

This will count as one of your downloads.

You will have access to both the presentation and article (if available).

DOWNLOAD NOW

This content is available for download via your institution's subscription. To access this item, please sign in to your personal account.

Email or Username Forgot your username?

Password Forgot your password?

Show

Keep me signed in

No SPIE account? Create an account

Proceedings Article | 21 August 2020 Presentation + Paper

Solc-style birefringent color filters based on multi-twist retarders

Lingshan Li, Shuojia Shi, Michael Escuti

Proceedings Volume 11483, 114830N (2020) https://doi.org/10.1117/12.2569133

KEYWORDS: Optical filters, Wave plates, Polarization

Read Abstract +

Birefringent color filters serve a critical role in next generation display systems, including augmented-/virtual- /mixed-reality headsets, and many types of optical remote sensing. Most prior polarization interference filters (PIFs) employ many individually aligned plates that enable only relatively thick color filters (≥ 100s of μm), are usually limited to small clear apertures (few cm), and offer poor off-axis performance. Here, we report on a family of monolithic, thin-film, birefringent PIFs formed using liquid crystal polymer (LCP) network materials, also known as reactive mesogens. These multi-twist retarders (MTRs) are only a few µm thick and have a single alignment surface. They offer high color saturation with a notch-type pass/stopband, analogous to Solc filters, and improved off-axis performance and large-area scalability. Here, we apply simplifying assumptions inspired by Solc-type PIFs, and develop a design method resulting in MTRs with an alternating achiral/chiral architecture. We design three representative color filters (blue-yellow, green-magenta, and cyan-red), and fabricate them. The resulting experimental films manifest strong color filtering behavior, with high saturation and uniformity. We study the color differences for oblique incidence, showing modest change within AOI ≤ 20°.

Proceedings Article | 20 August 2020 Poster + Paper

Color-selective geometric phase lens for apochromatic lens system

Lingshan Li, Jihwan Kim, Shuojia Shi, Michael Escuti

Proceedings Volume 11472, 1147219 (2020) https://doi.org/10.1117/12.2569165

KEYWORDS: Diffraction, Polarization, Liquid crystals, Colorimetry, Optical filters, Chromatic aberrations

Read Abstract +

Thin lenses have potentially much lower weight and volume than traditional refractive lenses, and therefore enable compelling solutions in augmented-/virtual-/mixed-reality (AR/VR/MR) headsets. The geometric-phase lens (GPL), formed either with liquid crystals (LCs) or metasurfaces, is emerging as a leading technology because of its ability to implement arbitrary aspherical phase profiles and its potential for low loss and minimal ghosting. However, a strong chromatic dispersion is inherent to each singlet. One prior method to overcome this employs a stack of multiple achromatic GPLs acting on all colors simultaneously with color filters and other waveplates to achieve an apochromatic lens system. Another concept in the prior art is to use multiple color-selective GPLs (CS-GPLs) wherein each diffracts only a single color while transmitting the others. In this work, we report on a family of color-selective GPLs with highly chromatic efficiency spectra, made using multi-twist LC coatings. In both theory and experiment, we show the diffraction efficiency of red, green, and blue lenses is high (< 91%) while the complementary colors of each coating are almost fully transmitted undiffracted. The CS-GPLs is a promising optical element to provide a new route to mitigate the chromatic abberation in the AR/VR/MR lens system.

My Library

You currently do not have any folders to save your paper to! Create a new folder below.

Folder Name

Folder Description

View contact details

UPDATE YOUR PROFILE

Is this your profile? Update it now.

Sign into your SPIE.org account

Don’t have a profile and want one?

Create an account on SPIE.org

Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks. You are receiving this notice because your organization may not have SPIE eBooks access.*

*Shibboleth/Open Athens users─please sign in to access your institution's subscriptions.

To obtain this item, you may purchase the complete book in print or electronic format on SPIE.org.

ORGANIZATIONAL
Sign in with credentials provided by your organization.

Organizational Username

Organizational Password

Show/Hide Password

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available

Members:

Non-members: ADD TO CART

Keywords/Phrases

Search In:

Publication Years