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We present, to the best of our knowledge, the first experimental investigation of a two-dimensional disk resonator on a dielectric multilayer platform sustaining Bloch surface waves. The disk resonator has been patterned into a few tens of nanometer thin (∼λ/25) titanium dioxide layer deposited on the top of the platform. We characterize the disk resonator by multi-heterodyne scanning near-field optical microscopy. The low loss characteristics of Bloch surface waves allowed us to reach a measured quality factor of 2×10^3 for a disk radius of 100 μm.

A subwavelength concentric ring metal grating for visible light (λ=632.8 nm) is designed and fabricated by electron-beam lithography to transform circularly polarized light into radially polarized light. Experimental results are compared to theoretical predictions and the advantages and disadvantages of the element with alternative methods are discussed.

A Moore 350FG 5-axis ultra precision machine tool platform with diamond tooling was used to generate 10 mm x 10 mm cylindrical diffractive lens on electroless nickel insert. An electroless nickel insert was machined by diamond turning and a diffractive collimating lens was cut by ruling with a sharp diamond tool. The path from optical designing to machining of the lens was proven. Selection of the tool type, stability of the cutting process and tool path programming play an important role in the outcome of the lens. This method will produce high quality diffractive lenses for further replication processes although great care must be taken in controlling the machining process stability.

We demonstrate good optical quality TiO_2 thin films grown by atomic layer deposition at 120°C. The optical properties were studied using spectroscopic ellipsometry and prism coupling methods. The refractive index was 2.27, and the slab waveguide propagation loss was less than 1dB/cm at 1.53μm. A high quality resonant waveguide grating was fabricated using a thin TiO_2 layer on top of a SiO_2 grating.

We employ interference microscopy to characterize in a direct and local way the graded index transitions at the boundaries of integrated optical elements fabricated by multistep ion-exchange processes, a task not yet possible by other technologies. A particular fabrication method based on purely thermal ion-exchange, which allows local single-mode propagation, is investigated. The refractive-index distribution is modeled on the basis of the linear theory of diffusion and adiabatic transitions of the refractive-index profile. Finally, its validity is analyzed by microinterferometry.

Different coding schemes for diffractive multilevel microlenses are compared. A simple method to code a lens to get the optimum diffraction efficiency is given. Furthermore, a straightforward way to estimate the achievable efficiency of a lens is presented.

A Moore 350FG 5-axis ultra precision machine tool platform with diamond tooling was used to generate v-shaped diffractive pattern on a refractive sinusoidal shaped structure. The refractive surface behaves like a cylindrical lens and the diffraction grating stretches the line focuses generated by the refractive surface. The structure was machined on an electroless nickel insert. The design and the simulation of the hybrid structure were performed using ray tracing and exact electromagnetic theory. The response of the grating was calculated by using Fourier modal method and the data was used in ZEMAX to calculate the amplitude and the phase of the diffracted rays.

This paper reviews the development of hydrogen silsesquioxane nanostructures (sub-100nm) on a silicon platform. The effect of HSQ resist in thick (128nm thick resist) and thinner state (30nm thick resist) has been demonstrated and minimum possible structures with these are discussed in details. Most applicable structures like straight lines/spaces, sharp joints/corners and dots were developed to investigate the effects of development time on the lithography properties of HSQ. Soft bake after spinning process had been avoided in view of achieving better contrast and stable resist deposition. We had also reached to a conclusion that increasing the development time could improve resist contrast and pattern resolutions up to certain limits but may vary with type of structures and other conditions.