surface roughness is a significant parameter which determines the efficiency of optical components. surface damages induced by grinding strongly influence the mechanical strength and optical quality of optical glasses. it is meaningful to rapid evaluate the surface roughness through the measurement of different grinding parameters. in this study, a cup diamond wheel (d64) is used in grinding pr...

Conventional material removal of BK7 optical glass will normally result in brittle fracture at the surface, generating severe subsurface damage and poor surface finish. Subsurface damages induced by grinding strongly influence the mechanical strength and optical quality of optical glasses. However, through ductile mode grinding it is possible to reduce the surface and subsurface cracks. It is m...

Conventional material removal of BK7 optical glass will normally result in brittle fracture at the surface, generating severe subsurface damage and poor surface finish. Subsurface damages induced by grinding strongly influence the mechanical strength and optical quality of optical glasses. However, through ductile mode grinding it is possible to reduce the surface and subsurface cracks. It is m...

Laser damage thresholds at 248nm of TiO,, ZrO, and HfO, thin films of h optical thickness on SQ1 quartz glass substrates are determined by the photoacoustic mirage technique. Damage thresholds correlate with the band gap energy of these materials, as determined by optical spectroscopy. It is demonstrated that the damage resistance can be raised by an additional h/2 SiO, overlayer. Damage thresh...

The interaction of laser radiation with dielectrics and metals is detected with femtosecond resolution by pump&probe techniques (t = 80 fs or 3 ps, λ = 810 nm). Even with femtosecond laser radiation melt ejection dynamics can be observed by irradiating metals like copper or aluminium using time-resolved shadowgraphy. Laser-induced melt ejection has been observed in the time range of 100 ns to 1...

Cross-phase modulation (XPM) and induced focusing occur when copropagating ultrafast pulses interact in a nonlinear medium. XPM and induced focusing are investigated as new techniques to control the spectral, temporal, and spatial properties of ultrafast pulses with femtosecond time response. In this paper we review our most recent measurements on (1) induced spectral broadening in BK7 glass, (...

A method to measure the propagation loss of optical waveguides is discussed. The measurement system involves two 3 dB couplers, a CCD camera and a signal processing unit. The propagation loss measured from this technique is found to be independent of coupling conditions. The propagation properties of waveguides prepared by proton exchange (PE) in Lithium Niobate (LiNbO3) and Silver ion exchange...

Frequency-resolved optical gating (FROG) is a technique that produces a spectrogram of an ultrashort laser pulse. The intensity and phase of the ultrashort laser pulse can be determined through solving for the phase of the spectrogram with an iterative, phase-retrieval algorithm. This work presents a new phase-retrieval algorithm that retrieves both the probe and the gate pulses independently b...

Ductile cutting are most widely used in fabricating high-quality optical glass components to achieve crack-free surfaces. For ultra-precision machining of brittle glass materials, critical undeformed chip thickness (CUCT) commonly plays a pivotal role in determining the transition point from ductile cutting to brittle cutting. In this research, cutting characteristics in nanometric cutting of B...

Incorporation of planar waveguide technology into a spectroelectrochemical sensor is described. In this sensor design, a potassium ion-exchanged BK7 glass waveguide was over-coated with a thin film of indium tin oxide (ITO) that served as an optically transparent electrode. A chemically selective film was spin-coated on top of the ITO film. The sensor supported five optical modes at 442 nm and ...