A volume hologram recorded with a lens array is proposed as a transflective screen for Head Worn Display (HWD)
systems. Design, fabrication as well as proof of concept are reported. Light from a projection system, with similar
properties to one mounted on the side of an eyewear, is efficiently diffracted towards the eye with an angular spread
given by the numerical aperture of the lenses forming the lens array. Using a dual-focus contact lens, high-resolution
images can be added to the HWD user’s normal vision, as light from the surrounding environment is transmitted through
the screen with low aberrations. This screen offers the possibility for small footprint and large field of view HWD’s.
Enhanced optical transmission (EOT) through subwavelength apertures is usually obtained for p-polarized light. The
present study experimentally investigates EOT for s-polarized light. A subwavelength slit surrounded on each side by
periodic grooves has been fabricated in a gold film and covered by a thin dielectric layer. The excitation of s-polarized
dielectric waveguide modes inside the dielectric film strongly increases the s-polarized transmission. Transmission
measurements are compared with a coupled mode model and show good qualitative agreement. Adding a waveguide can
improve light transmission through subwavelength apertures, as both s and p-polarization can be efficiently transmitted.
The miniaturization of photodetectors often comes at the expense of a smaller photosensitive area. This can reduce the
signal and thus limit the image quality. One way to overcome this limitation is to reduce the photosensitive area but with
no reduction of signal i.e. harvest the light. Here we investigate, theoretically and experimentally, light harvesting with
nanostructured metals. Nanostructured metals can also give additional functionality such as polarization filtering which
is also investigated. After defining the figure of merits used when characterizing light harvesting and polarization
filtering structures, we detail the fabrication and measurement process. Structures were made on glass substrate, as a post
process step on CMOS fabricated detectors and directly in the CMOS fabrication of the detectors. The optical
characterization results are presented and compared with theory. Finally, we discuss the challenges and advantages of
integrating metallic nanostructures within the CMOS process.
In this paper, we show that a two-dimensional random system can display strong structural colors in transmission.
Polystyrene microspheres with a diameter between 0.5 and 1μm have been randomly adsorbed onto a glass substrate. In
this size range, light is mainly scattered in the forward direction. Consequently, in-plane multiple scattering can be
neglected while spheres are not too close to each others. This allows one to use a single scattering approximation to
reproduce transmission spectra of the system. Under appropriate conditions, destructive interferences between incident
and scattered light can cause a full extinction in the transmission. In our case, transmission can be as low as 5% at some
frequency ranges, generating strong color effects. Additionally, the film color changes with the angle of observation.
This angular dependant color is reproduced theoretically taking into account multiple scattering between spheres.