Design of a freeform gradient-index prism for mixed reality head mounted display

Yee, Anthony; Song, Wanyue; Takaki, Nick; Yang, Tianyi; Zhao, Yang; Ni, Yunhui; Bodell, S. Yvonne; Rolland, Jannick P.; Bentley, Julie; Moore, Duncan T.

doi:10.1117/12.2307733

Cited by 10 publications

(4 citation statements)

References 6 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…One of the primary benefits of GRIN fabricated via additive manufacturing is the ability to vary the refractive index radially and axially within the same lens. Numerous design studies have shown the utility of refractive index distributions that vary along two independent spatial dimensions [44][45][46][47]. And more recently, their usefulness in multi-material F-GRIN systems has also been demonstrated [31,32].…”

Section: Axially-dependent Multi-materials Grin; or Multi-materials F...mentioning

confidence: 99%

See 1 more Smart Citation

Exploring the unique chromatic properties of multi-material gradient-index optics

Desai,

Schmidt,

Moore

2024

Optical Design and Engineering IX

Self Cite

View full text Add to dashboard Cite

Traditionally, gradient-index (GRIN) optics have been made by varying the ratio of two distinct materials or exchanging two components within a base material. This has largely been dictated by manufacturing methods. However, due to recent advancements in additive manufacturing, GRIN optics can now be composed of a blend of multiple materials (i.e., more than two). It can be shown that these new, multi-material GRIN optics possess numerous advantages over traditional GRIN optics, especially in the realm of color correction.Such advantages arise due to multi-material GRIN's ability to separately vary the GRIN power and the GRIN dispersion, a feat not possible with only two materials. Additionally, when the GRIN power is allowed to vary along the optical axis, the GRIN dispersion can also vary along the optical axis. This means that a single multi-material GRIN element can have regions of both positive and negative dispersion and regions that are extremely dispersive or nearly dispersionless. The ability to spatially tune the dispersion within a single optic is a powerful design tool which will be highlighted in this paper.

show abstract

Section: Axially-dependent Multi-materials Grin; or Multi-materials F...mentioning

confidence: 99%

“…Much of this analysis is not new [31,32] or unique to multi-material F-GRIN (in that binary F-GRIN can achieve this effect as well) [44][45][46][47]. What is new and unique to multi-material F-GRIN is the idea that, when axial-dependence is introduced, the 𝑉 "#$% and 𝑃 "#$% can also vary in 𝑧.…”

Section: Legendre Term Functional Formmentioning

confidence: 99%

Exploring the unique chromatic properties of multi-material gradient-index optics

Desai,

Schmidt,

Moore

2024

Optical Design and Engineering IX

Self Cite

View full text Add to dashboard Cite

show abstract

“…A freeform refractive index distribution within a lens causes an optical path difference to transmitted light that is analogous to the function of one or more freeform surfaces (depending on thickness, distribution, and index variation). Freeform-GRIN media have only recently been applied to imaging problems of non-rotationally symmetric systems, 8,9 demonstrating promise in the optical design of a freeform prismatic display. Additionally, freeform-GRIN lenses have been experimentally demonstrated by Yang et al 10 to reduce the aberrations of a tilted spherical mirror.…”

Section: Introductionmentioning

confidence: 99%

Optical design of a freeform, gradient-index, head-mounted display

Boyd

2023

Opt. Eng.

View full text Add to dashboard Cite

.I present the results of an optical design study into the performance benefits of non-rotationally symmetric “freeform” gradient-index (GRIN) media on a pupil-relay head-mounted display. A range of design variants are presented based on freeform-GRIN lenses consisting of ternary base-material combinations that are enabled by recent developments in additive manufacture. The optical performance of these designs is compared to homogeneous solutions comprising combinations of spherical, aspheric, toric, and freeform surfaces. I show that freeform-GRIN media represent powerful degrees of freedom for aberration correction in tilted and off-axis optical systems, performing comparably to homogeneous freeform optics while illustrating significant potential reductions in lens count and mass.

show abstract

“…In order to simplify the optical system before the sensor and to keep high image quality, optical designers have to find new degrees of freedom in their designs. Several ways are thus explored like freeform optics [1], GRIN (gradient index) optics [2] and metasurfaces [3].…”

Section: Introductionmentioning

confidence: 99%

Femtosecond laser direct writing of a Fresnel zone plate in glasses for mid-infrared imaging applications

et al. 2021

View full text Add to dashboard Cite

An important challenge in infrared imaging today consists in addressing the SWaP problem (Size, Weight and Power), for example by simplifying as much as possible the optical system before the sensor. The work presented in this paper takes advantage of recent techniques in femtosecond laser direct writing to imprint optical systems.This work aims at merging a lens array with a filter array by writing gradient index lenses with a femtosecond laser inside a dedicated glass substrate. A classical gradient index lens requires a huge refractive index variation, which cannot be reached today with femtosecond laser processing (Δ𝑛 𝑚𝑎𝑥 ~ 0,05). So, we decided to turn towards writing a gradient index Fresnel lens. A first-order Fresnel lens was designed with a Δ𝑛 𝑚𝑎𝑥 < 5.10 −2 discretised into 8 index levels to guarantee a diffraction efficiency of 85% on the overall spectral bandwidth of the filters.We studied a chalcogenide glass because of his good properties in mid-IR optics. We compared the different laser responses of the material: threshold of permanent changes, quantitative phase and index variation.Finally, we showed that reaching a phase variation of 𝜋 radians with femtosecond laser writing is possible even for a huge scanning speed (0,01 mm/s up to 25 mm/s). By overlapping the written lines, we were able to implement a maximum phase variation of 8 radians (with only one written layer), demonstrating the possibility to write quickly a GRIN Fresnel lens with a diameter of some millimeters.

show abstract

Design of a freeform gradient-index prism for mixed reality head mounted display

Cited by 10 publications

References 6 publications

Exploring the unique chromatic properties of multi-material gradient-index optics

Exploring the unique chromatic properties of multi-material gradient-index optics

Optical design of a freeform, gradient-index, head-mounted display

Femtosecond laser direct writing of a Fresnel zone plate in glasses for mid-infrared imaging applications

Contact Info

Product

Resources

About