The design, fabrication and properties of various types of optical waveguides on silicon substrates as well as Fabry- Perot devices accomplished mainly at the Microelectronics Center of VTT Electronics are introduced. Different waveguides, directional couplers, multimode interference couplers, switches and power splitters have been studied. For waveguide fabrication on silicon substrates principally three materials were used depending on the application: silicon oxynitride, silicon on insulator (SOI). Silicon waveguides with large Si-core and a thermo-optical switch have been fabricated by SOI technology. Silicon Fabry-Perot structures have been fabricated for wavelength scanning applications in instrumentation and to measure chirp properties of lasers used in optical communications.

An investigation of a series of low-power thermo-optic phase-modulating devices fabricated in SIMOX material suitable for use in distributed sensing or as optical variable attenuators is presented. These devices are integrated in a balanced Mach-Zehnder Interferometer utilizing multi-micron vertical sidewall rib waveguides and exhibit low polarization dependence. The investigation highlights the power consumption of various lengths of devices with low-lateral heat diffusion operated by ohmic heating and quantifies the attainable modulation depths under quasi-static operation. Non-linear device behavior is demonstrated and explained with a proposal for these characteristics giving rise to devices which would operate with further power reductions. AC characteristics are also investigated, showing the modulation to have 3 dB bandwidths of approximately 40kHz. A second device geometry is presented which was fabricated utilizing an under-etching technique to suspend the arms of the Mach-Zehnder. Results indicate lower power operation with a corresponding reduction in bandwidth to approximately 1kHz. An improvement in overall device geometry provides modulation depths in excess of 99 percent, independent of both bandwidth and power.

A new type of non-perturbing electromagnetic power sensor for microwaves and millimeter-waves, based on the thermo- optical effect in a silicon interferometric etalon cavity is presented. The incident field power is partially dissipated into the all-silicon metal-less etalon, constituting the sensing element of the detector, so causing its temperature increase. This, in turn, induces the intensity modulation of a probe laser beam reflected by the cavity after a multiple beam interference process. The sensing element is directly connected to an optical fiber for remote interrogation, so avoiding the use of perturbing coaxial cables. The performances of such a new class of non-perturbing and wideband probes, in terms of sensitivity and resolution are discussed in detail. The experimental results concerning the characterization of a preliminary prototype sensor are presented and compared with theoretical data. The dependence of the sensor response on the electromagnetic frequency and on the sensing element characteristics is finally discussed.

Silicon-on-Insulator (SOI) is an attractive platform for fabrication of photonic bandgap devices. The large refractive index step between the silicon waveguide and the SiO₂ lower cladding layer permits realization of periodic waveguides with very large index modulation. The large refractive index modulation is obtained by deep anisotropic etching into the silicon guide region, and makes it possible to obtain strong resonances in compact periodic structures with only a few periods. In addition, the processing of these structures is highly compatible with standard silicon CMOS processing. Hence this technology is attractive for low cost, highly integrated photonic and optoelectronic circuits.

Traditionally, there were two fabrication processes for LiNbO₃ ridge waveguides, which were nickel (Ni) diffusion prior to PE wet etch, the DE process, and PE wet etch prior to Ni diffusion, the ED process. Though these processes have been optimized and are much better than the dry etch methods, further improvement is necessary. This is because the former easily result in unwanted planar waveguides flanking the ridge structures, while the latter requires relatively complicated process. In this paper, a novel self-aligned fabrication process for Ni:LiNbO₃ ridge waveguides has been proposed. By using the self- aligned tri-layered structure composed of Ni/Ti/Si, the fabrication process is significantly simplified. Based on our observations, the deposited thickness of the self- aligned structure will determine the qualities of the ridge waveguides. Moreover, the novel self-aligned fabrication process was applied to fabricate a ridge waveguide Mach- Zehnder modulator. The measured half-wave voltage and extinction ratio were 20.5V and 12dB, and were 4.2V and 8dB.

We demonstrate a GaAs/AlGaAs multiple-quantum-well in-line fiber optic intensity modulator. Based on evanescent wave coupling between a GaAs/AlGaAs anti-resonant reflective optical waveguide and a side-polished single mode fiber, this device concept combines the inherent advantages of in- line fiber devices with high-performance GaAs integrated optoelectronics. The GaAs waveguide utilizes distributed Bragg reflector mirrors, which are designed to provide maximum reflection at a given more angle, to phase-match to the low-index fiber. Intensity modulation of the transmitted light through the fiber is achieved by changing the complex propagation constant of the GaAs waveguide through the quantum-confined Stark effect. Typical device shows an on/off ratio of 4:1, with an applied voltage of 9V. Calculations show that with a longer interaction region, an on/off ratio of more than 40dB is achievable with the same applied voltage.

Nonlinearity of Electroabsorption modulator (EAM) resulting from its near exponential transfer function decreases SNR in analog optical transmission. Since the transfer function of semiconductor optical amplifier (SOA) is inverse to that of EAM, the intermodulation distortion of EAM can be reduced by using SOA that connect with EAM in series and operating in gain saturation region. To improve the nonlinearity compensation of EAM, the increased gain of SOA is required and the slope of giant saturation, the ratio of gain to input SOA power, needs to be steep. However, the signal- spontaneous beat noise that is the dominant system noise increase in proportion to the gain. Thus, the noise power level of system is increased and the spurious free dynamic range (SFDR) of EAM is reduced. We have analyzed the SFDR variation of EAM including SOA gain and ASE noise. An enhancement of 9dB in SFDR was theoretically obtained and the gain of SOA for an optimum operation is mentioned. The proposed scheme is easy to implement and can be monolithically integrated with other optical devices useful for an efficient linear analog optical transmitter.

A novel filter with tunable bandwidth and wavelength is introduced. Its bandwidth can be tuned by a transverse voltage. And its wavelength can be tuned by a longitudinal voltage. The main parameters that affect its properties are synthetically analyzed. Computer simulation results show that its transmission bandwidth is changeable and the transmission spectrum with rectangular working area is close to the ideal band-pass function. Experimentally, its free spectral range is more than 50nm. The tunable range of the center wavelength is about 50nm. The full width at half maximum can be tuned from 1.2nm to 50nm.

The increasing diffusion of WDM communication systems requires low cost and efficient optical add-drop devices to add or drop channels at predefined wavelengths with reduced insertion loss and cross-interference. Many fiber based devices have already been proposed, however their integration allows an increase in the compactness and mechanical stability. We designed an integrated OADM that is composed of an asymmetric adiabatic transition followed by an asymmetric grating that converts the supermodes of the combined structure. In this paper we focus our attention mainly on the design of the transition that, besides having low insertion losses, should also be tolerant to the variation of the fabrication parameters and in particular of the grating position. Assuming typical glass on silica waveguides, the transition geometry has been determined using the coupled mode theory. Then the result have been verified and optimized with BPM simulations.

A novel approach to characterizing integrated optical waveguides is described in which laser light illuminates the surface normal of the waveguide substrate and the transmitted light observed in the far field uniquely describes a number of physical characteristics of the waveguide. The proof of concept has been demonstrated with a HeNe laser on an ion diffused waveguide in silica glass but the technique is applicable to any integrated otpical waveguide. The advantages of this approach are that it is a great deal less expensive than conventional approaches using a Nemarski microscope or an EDAX attachment to an electron microscope and is very simple to set up. The small index variations that comprise a waveguide on a substrate are normally invisible . However, using this technique, when laser light is scanned across the waveguide, a unique pattern is seen in the far field that can be interpreted to not only determine the location of the waveguide, a unique pattern is seen in the far field that can be interpreted to not only determine the location of the waveguides but also certain physical characteristics about them.

The Vectorial Modulation Transfer Function (VMTF) calculation will be used for the explanation of diffraction patterns obtained with Brewster ellipsometers. The method used to study these phenomena lays on protection of the incident monochromatic distribution on a basis constituted of monochromatic plane wave components. The first point examined is how the plane wave spectrum could be propagated through a polarizing pate considering the polarization distortions introduced by diffraction. The same calculation is realized for the whole system in order to establish the expression of the whole VMTF. Paraxial approximations are used in order to analyze more easily the reflected beam pattern and to compare it with experimental results. The good agreement between experimental results and model allows a quantitative valuation of index measurement accuracy as a function of the interface mean surface roughness of the experimental sample considering the specular reflection on the homogeneous plane interface. Taking into account the amount of light scatter by the interfaces irregularities it is then possible to specify the theoretical uncertainties limits affecting as well refractive index and refractive index gradients measurements.

In order to develop a nondestructive technique for inspection of optical-grade LN wafers used as substrate to fabricate optoelectronic devices such as electro-optic modulator, a scanning IR polariscope (SIRP), which was developed to measure a small amount of residual strain in optically isotropic GaAs wafers, has been employed. It is demonstrated that the sensitivity of SIRP adopted for LN wafers is high enough to detect the change in refractive index caused by crystal defects, down to the order of 10^-7. X-ray topography measurement is also carried out to confirm the usefulness of SIRP as an inspection tool of crystal defects in optical-grade LN wafers.

We report the theoretical performance of a digital switch based on a wide-angle, low-loss asymmetric X-junction we recently proposed. At a full-branching angle of 1.2 degrees, the cross-talk and transmission at the zero-voltage state have been -20 and -0.5 dB, respectively. In the switched state, they are -19.5 and -1.1 dB, respectively.

Results form our near-surface approach for inhomogeneous films are compared with those from the standard m-line technique in K⁺ and Ag⁺ ion-exchanged, graded- index waveguides. We focused our attention on the determination of the refractive index at the film-air interface, and we conclude, from fundamental reasoning as well as from experimental evidence, that the direct near- surface approach can provide higher accuracy than the usual extrapolation from the modal effective indices.

An inductively coupled plasma torch has been used for the synthesis of high-purity, low OH concentration, fused silica layers, for integrated optics applications. This technique is very versatile and the same apparatus can be used to deposit silica layers doped with different elements but this work is particularly devoted to the germanium-doped silica layers. The torch, designed and built in-house, operates at atmospheric pressure and is posed by a 13.56 MHz, 5.4 kW, RF generator. The gaseous reactants are injected in the plasma tail flame by a silica nozzle. Planar silica targets are suitably moved over the torch exit in order to obtain the desired deposition. The samples made by means of this chemical vapor deposition process have been chemically and physically analyzed using various techniques: optical microscopy, scanning electron microscopy, atomic force microscopy, x-ray diffractometer, UV, visible and IR spectroscopy, to test their morphological, geometrical, chemical and optical characteristics. By this plasma- assisted technique it has been possible to achieve the deposition of pure and germanium doped silica layers with good optical and morphological characteristics. Preliminary direct UV photoinduction experiments are very promising: a high refractive index change has been measured.

The potential of 3D integrated optics based on different technological schemes is investigated. Theoretical and experimental results for waveguide geometries with stacked waveguide layers and with waveguide circuits prepared on topological structures are reported as well. Within waveguide geometries including individual guides in a sequence of stacked layers directional coupler arrays allow for short length passive signal distribution, and various schemes of single and multipath switching can be identified. Cost effective preparation technologies as spin coating of polymer and PECVD of SiON layers and their patterning by UV- exposure or RIE, respectively, have been prove to fulfill the critical tolerance requirements of a simultaneous directional coupling in two transversal directions. To realize waveguides with smooth height variation gray scale lithography was used to produce topological surfaces. Upon those surfaces waveguide paths and devices can be defined subsequently, which are useful e.g. for non-planar to planar fan out structures or interferometer configurations for sensing applications. The topological surfaces can be replicated very efficiently by reaction molding, a technology widely used for micro-optical structures, too.

Ion beam etching (IBE) and chemically assisted ion-beam etching (CAIBE) of InP wafers are studied. While Argon alone is used for the IBE process, the CAIBE is carried out by using Ar/H₂CH₄. The realization of CAIBE in Ar/H₂ atmosphere is also achieved for the first time. The evolution of the surface roughness and morphology is presented comparatively by varying acceleration voltage (V_acc), discharge current (I_dis) and ion incidence angle. A drastic improvement of the surface roughness is obtained for the CAIBE using Ar/H₂ chemistry. The etch rate of the InP structures is studied as a function of the I_dis and the V_acc. A maximum etch rate of 700 angstrom/min is observed for 1.75kV acceleration voltage and 45 mA discharge current at 30 degrees ion incidence angle. The variation of the etch rate against the ion incidence angle is investigated both theoretically and experimentally. A good agreement between those is observed. Finally, the anisotropy of InP samples is presented for two different masks; Al₂O₃ and Titanium in the case of CAIBE mode. The most anisotropic structure of 83 degrees is performed by using the Ti mask.

An efficient method, the high temperature proton exchange (HTPE), to fabricate high-quality LiNbO₃ optical waveguides is studied. The new proton exchange source, the stearic acid diluted by lithium stearate, is proposed for HTPE process. The known Soft Proton Exchange (SPE) process can be realized by HTPE. THere are no phase transitions when the (alpha) -phase waveguides are fabricated by SPE. This phase presents the same crystalline structure as that of LiNbO₃ and, as expected, maintains the excellent nonlinear and electro-optical properties of the bulk material. The kinetics of HTPE is studied.

We show that SiO₂ cladding effects on optical properties of annealed proton-exchanged (APE) LiNbO₃ waveguides as well as on kinetic of annealing process. Annealing with previously deposited SiO₂ film reduces the optical losses in APE LiNbO₃ waveguides. The structural phase diagram of H_xLi_1-xNbO₃ is also modified if annealing is performed with previously deposited SiO₂ layer. The physical mechanisms, including evaporation of H₂O and/or Li₂O during annealing without deposited film and, as a result, formation of defects and lithium deficit phase is discussed.

We present a technique to directly process silver ion- exchanged planar waveguides fabricated in soda-lime glass. The technique, that is regarded as complementary to the conventional lithography but with the inherent advantages of the direct processing of the material, is based on laser writing with a focused laser bema from an Ar⁺ laser, which induces a redistribution and aggregation of the small sliver clusters created in the glass during the ion-exchange process. We give a theoretical explanation of the physical processes that take place in the glass and expose experimental reslut of processing of silver ion-exchanged guides under different irradiation conditions. We expose the possible applications of this technique to integrated optics for 2D waveguiding, to optoelectronics for one-step electrode and waveguide fabrication, to planar optics for patterning of reflective components and to diffractive optics to fabricate conventional elements. We finally demonstrate some of this applications presenting devices fabricated by means of this technique.

Frequency conversion efficiency limiting factors in PPKTP crystals and segmented waveguides have been investigated. It was found that at high intensity, back conversion effects related to the spectral and spatial properties of the laser beam, limit the conversion efficiency. High conversion efficiencies in PPKTP are demonstrated by selecting proper laser conditions. A parametric study of the influence of geometrical parameters on conversion efficiency in periodically segmented waveguides has been carried out and an optimal design parameter range has been defined. An improved waveguide structure in which higher efficiencies can be obtained is suggested.

Quasi-phase-matched (QPM) LiNbO₃ waveguides are at present the most efficient device for second-harmonic- generation (SHG). They require the periodic inversion of the ferroelectric domains and the fabrication of annealed- proton-exchanged (APE) waveguides. In order to work at a wavelength of interest for telecommunications, 1300nm, we realized an APE waveguide, single-mode at such wavelength, on a periodically-poled substrate with a period of 11.7 micrometers . Domain inversion was obtained by Ti-indiffusion. The sample was linearly characterized. For the nonlinear experiment, a tunable Nd:YAG-pumped OPA was used as the light source. The maximum efficiency for SHG was found around 1300nm, within a few nanometers from the expected wavelength. The ratio among the output power of the second harmonic and of the fundamental guided mode was 56 percent. Together with the SH, the third harmonic was generated as the result of a (chi) ² cascading process. On the basis of the result obtained, the problems connected with the design and fabrication of QPM devices will be discussed, with particular attention to the tolerance sin waveguide fabrication. It is worth noting that the two wavelengths were generated simultaneously, using a single laser source. This opens the possibility of generating multicolor output in diode-pumped QPM-waveguides.

A brief overview of some recent results in the fabrication and characterization of optical guiding structures based on thin films of lithium fluoride is presented. These LiF structures are being developed with the main aim of obtaining an integrated broad-band tunable lasers operating in the visible spectrum. Properties and perspectives of this approach are also discussed.

This paper outlines implementation options for integrated optical components within current and future communications systems, with an emphasis on Lithium Niobate optical modulators and other transmission components.

Ion-Exchanged Glass Integrated Optics has received a considerably attention during the laser years because of their well-known advantages. On the other hand, ion- exchanged waveguide components are finding important applications in the implementation of analogue processing devices, optical sensing devices and some kind of circuit for optical communications. Many of these develop devices are based on channel guides, however planar components with optical confinement in only one dimension have been also recognized to be among the basic components of glass integrated optics. In this paper we show the specific advantages of using these kinds of integrated optical elements. Thus, conventional photolithographic techniques can be used with a great accuracy but within the high requirements needed for channeled devices. Likewise, as it will be shown, the components can be realized by simple selective ion-exchange processes in a few steps, and with a high transmission of guided light, in a monomode regime, through the various boundaries shaping the planar components. Finally, their planar configuration facilitates considerably the use of glass integrated devices with other materials and thus a high-performance hybrid optical devices can be achieved. In short, we show various approaches to the design and fabrication of planar components and presents several passive components implementing simple functions such as: beam-splitting, focusing, and so on, which are important for optical sensing and processing applications.

This paper shows the demonstration of Multimode Interference (MMI) power splitters with graded index waveguides using ion-exchange technology. Typically these devices have been fabricated using step index waveguides such as silica waveguides on silicon. The advantages of ion-exchange technology and MMI splitters fabricated by ion-exchange are discussed. The design and simulation results for a 1*4 MMI splitter are presented and compared to the experimental results.

Self-guided waves that can be excited in quadratic nonlinear media have been extensively studied for their potential applications in ultra-fast all-optical processing. We have previously reported the use of solitary waves collision in a KTP crystal to experimentally demonstrate all-optical switching of IR picosecond pulses. Up to now, the intensity required to obtain self-trapping of a beam remained at a high level. This has been due to the lack of nonlinear crystals which combine the attributes of a large nonlinearity and phase-matching capability at experimentally convenient wavelengths. The availability of Periodically Poled Lithium Niobate can circumvent this difficulty. 2D spatial solitary waves in PPLN have been predicted theoretically and simulated numerically. In this communication we will report their experimental observation and for the first time their interaction in a 15mm long crystal. Then we will compare solitary wave behavior in KTP and PPLN, in particular self-trapping intensity threshold versus phase mismatch. We will also compare experimental data with the reslut of our computations modeling. In a last part we will show our first experimental result about 2D quadratic soliton collision in a PPLN crystal. Finally we will discuss the advantages of choosing PPLN to realize all- optical devices using solitary wave interactions.

The solitons have to satisfy the requirement of being self- guided in bulk media in view of their potential applications in information processing, photonic switching and all- optical digital logic. Therefore, there is a growing interest for spatiotemporal solitons, characterized by a balance of diffraction and dispersion with respectively nonlinear spatial and temporal self-focusing. Such solitons are called 'light bullets.' Due to their complete localization in space and time and low energy easy to be dissipated, light bullets appear to be the best candidate for carrying the information that has to be treated in all- optical logic circuits. However, such pulses are inherently unstable to propagation in Kerr media. We consider the conditions for the light bullets generation in the media with saturating nonlinearity, like polydiacetylene para- toluene sulfonate. The simulations show that the pulse above critical energy is trapped provided its initial parameters belong to the range reasonably close to the one predicted by our analytical approach. Thus, in spite of the initial asymmetry in the final stage of evolution the symmetric stable pulse i.e., light bullet will be formed. Light bullets are exceptionally robust self-guided objects that can be generated even far form stable equilibrium. The initial pulse parameters without restrictions on their symmetry and their vicinity to the equilibrium are much less involving to realize in an experiment. The influence of the modulation instability is also considered.

Wavelength conversion is a key function in wavelength- division multiplexing. Frequency-shifting can be obtained through cascaded second-order nonlinear processes: a pump at (omega) is coupled into the waveguide, second harmonic is generated and made to interact with a coupled signal at (omega) -(Delta) (omega) so as to obtain a converted signal at (omega) + (Delta) (omega) via difference frequency generation. For practical applications, it is essential to achieve a good control in waveguide fabrication so as to be able to design a frequency-shifting device for specific pump and signal frequencies. In this work we report frequency- shifting based on cascaded second-order nonlinear processes obtained in simple planar Ti-undiffused LiBnO₃ waveguides, where phase-matching is achieved by birefringence. A Y-cut planar waveguide, 17mm long, was fabricated by diffusing a 290-angstrom-thick titanium layer for 6 hours at a temperature of 1000 degrees C. Thanks to a good modeling of the fabrication process, the waveguide behavior could be predicted directly from the fabrication parameters. A converted signal at 1.100 micrometers was obtained from a pump at 1.104 micrometers and a signal at 1.108 micrometers at a working temperature of 85 degrees C. The phenomenon was observed with a reasonable efficiency and was highly reproducible. The experimental results were in very good agreement with the expected ones.

We propose and demonstrate a new and simple technique for characterization of fast third order optical nonlinearity of wave-guides and bulk materials. Z-scan method, proposed and developed or bulk materials, has been preferred by experimentalists. It investigates nonlinear spatial distortion induced on a focused laser beam. In fact the technique that we present here, which we have called 'D- scan', is the temporal analog of the spatial Z-scan. It is based on spectral changes of a femtosecond pulse according to the dispersion preliminary introduced on the input femtosecond pulse by a dispersive delay line. The nonlinear evolution of the output spectrum when the dispersion introduced at the input is varied from negative to positive gives a sensitive measurement of the complex third order nonlinearity. The imaginary part of nonlinear susceptibility can be deduced from the evolution of the total average transmitted power versus the input dispersion. More, the plot of the position of center of the output spectrum may be exploited to measure the refractive index change time response. In order to demonstrate the capability of the proposed method we have experimentally retrieve the standard value of the nonlinear coefficient n₂ of silica during characterization of a short samples of a single-mode optical fiber.

The periodically segmented waveguide (PSW) has been used for a variety of applications, including frequency conversion, filtering, mode expansion and evanescent wave sensing. The PSW functionalities include index averaging and linear/nonlinear index grating, with the advantage of an inherent single-step fabrication. The paper briefly reviews some aspects of the PSW, and then focuses on a new type of segmented waveguides, and on applications of the PSW for biosensing.

IntelliSense has developed an integrated optic gyro technology that provides the sensitivity of fiber optic gyros while utilizing batch microfabrication techniques to achieve the low cost of mechanical MEMS gyros. The base technology consists of an optical resonating waveguide chip, sensor electronics and an optical bench. The sensing element is based on an integrated optic waveguide chip in which counter-propagating optical fields are used to sense rotation in the plane of the waveguide through the Sagnac effect. It is powered by a semiconductor laser light source, which is coupled into a waveguide and split into two waveguide arms. Both signals are probed through the out coupled light at each waveguide arm, and rate information is derived from the difference in phase between these two signals. Measuring angular rotation is important for proper operation of a variety of systems such as: missile guidance systems, satellites, energy exploration, camera stabilization, robotics positioning, platform stabilization and space craft guidance to mention a few. This technology overcomes the limitations that previous commercially available gyros for this purpose have had including limitations in size, sensitivity, durability, and premium price.

A novel neural network based technique instead of now available measures to raise FOG's measurement precision was proposed in the paper. The technique includes a few of aspects: a series-single-layer neural network used for dealing with the random noises, an advanced learning scheme corresponding with the above network, and an RBF network based method to evaluate the temperature drift. The series- single-layer network, which is composed of two single-layer networks in series, has advantages of simple architecture, fast learning speed, and better performance over conventional BP networks. To conduct the learning of the series-single-layer network, the advanced learning scheme derived from drawing the increments of error into energy function was then developed after referring to the unstable power law noise. Furthermore, in consideration of their good performances, we introduced an RBF network to evaluate and compensate the temperature drift and selected OLS algorithm to construct the network with high speed. The simulation results verified the validity that the proposed technique greatly decreased the errors induced by the different random noises and the biasing drift existing in FOG system.

We have theoretically and experimentally investigated the fundamental characteristics of glass-based integrated optic pressure sensors with a conventional Mach-Zehnder (MZ) interferometer and with an intermodal (IM) interferometer consisting of a straight waveguide. Each sensor has a rectangular diaphragm as a pressure-sensitive mechanical structure. The sensing path of the MZ interferometer and the waveguide of the IM interferometer should be placed along the diaphragm edge to maximize the sensitivity of the sensors based on the elasto-optic effect. IF the deflection of the diaphragm is small, the phase difference either between the sensing and reference waves for the MZ interferometer or between the fundamental TM-like and TE- like modes for the IM interferometer is proportional to the applied pressure. The sensors were fabricated using two glass substrates: a 0.3mm-thick Corning 0211 glass and a thick soda-lime glass with a 10mm X 10mm hole. After forming the waveguide on the 0211 glass, both substrates were bonded together with optical cement. For each sensor, the dimensions of the diaphragm were 10mm X 10mm X 0.3mm and the interaction length was 10mm. The sensitivities measured at 633nm in wavelength were 0.053rad/kPa for the MZ interferometer using the TM-like mode and 0.041rad/lPa for the IM interferometer. Each result was, however, half its theoretical estimate.

A new family of UV curing Aerobic Acrylic adhesives has been developed and positioned specifically for optical assembly applications. The development of this new optical adhesives line is the result of a strong response to and use of industrial grades of Aerobic Acrylic adhesives by various companies in the optical industry. The purpose of this paper is to introduce the new product line to the optical assembly industry and describe the features and benefits it has to offer. The paper will discuss significant benefits of the new optical adhesives including: Higher strength bonds - comparable to epoxies; Faster cures than typical optical grade UV curing mercaptoesters; Low stress, high strength bonds lead to superior durability; Where they may be used to replace slower curing adhesives; and How Aerobic Acrylic formulations achieve these benefits.