Showing papers on "Tilt (optics) published in 2000"

Analysis and synthesis of intonation using the Tilt model

Abstract: This paper introduces the Tilt intonational model and describes how this model can be used to automatically analyze and synthesize intonation. In the model, intonation is represented as a linear sequence of events, which can be pitch accents or boundary tones. Each event is characterized by continuous parameters representing amplitude, duration, and tilt (a measure of the shape of the event). The paper describes an event detector, in effect an intonational recognition system, which produces a transcription of an utterance's intonation. The features and parameters of the event detector are discussed and performance figures are shown on a variety of read and spontaneous speaker independent conversational speech databases. Given the event locations, algorithms are described which produce an automatic analysis of each event in terms of the Tilt parameters. Synthesis algorithms are also presented which generate F0 contours from Tilt representations. The accuracy of these is shown by comparing synthetic F0 contours to real F0 contours. The paper concludes with an extensive discussion on linguistic representations of intonation and gives evidence that the Tilt model goes a long way to satisfying the desired goals of such a representation in that it has the right number of degrees of freedom to be able to describe and synthesize intonation accurately.

Rearview mirror assembly with internally mounted compass sensor

Abstract: A rearview mirror assembly (100) is disclosed for use in a vehicle that includes a mirror housing (120), a mounting structure (200) for pivotally mounting the mirror housing to the vehicle such that the mirror housing may be both vertically and horizontally tilted, a compass sensor (320) disposed in the mirror housing and coupled to a compass processing circuit. The mirror assembly may include means (380) for compensating for tilting of the mirror housing and may include a tilt detector (500) for detecting when the mirror housing has been tilted from a prior position.

Steering column adjustment system using force feedback system

Abstract: An automotive vehicle steering column ( 10 ) and adjustment system has a telescope adjustment mechanism for adjusting the fore-aft position of the steering wheel ( 12 ) to the driver of the vehicle and a tilt adjustment mechanism for adjusting steering wheel inclination. Each adjustment mechanism includes a respective motorized linear actuator ( 24, 26 ). A force feedback system operates the actuators and includes telescope and tilt sensors ( 42, 44 ) for sensing telescope and tilt adjustment forces externally applied to the steering wheel by the driver during adjustment of steering wheel position. A controller ( 40 ) is responsive to the sensors for operating the actuators to position the steering wheel in directions of adjustment corresponding to the directions of telescope and tilt forces applied by the driver. Adjustment motion stops when the externally applied forces causing the motion cease.

Electroclinic liquid crystals with large induced tilt angle and small layer contraction

Abstract: Optical and x-ray scattering studies of a chiral, organosiloxane smectic-A liquid crystal indicate a large field induced optical tilt of up to 31 degrees accompanied by a very small contraction of the smectic layers. This result suggests that the molecules have a nonzero tilt even with no applied field, and that the primary effect of the field is to induce long range order in the direction of the molecular tilt.

Tilt Aftereffects in a Self-Organizing Model of the Primary Visual Cortex

Abstract: RF-LISSOM, a self-organizing model of laterally connected orientation maps in the primary visual cortex, was used to study the psychological phenomenon known as the tilt aftereffect. The same self-organizing processes that are responsible for the long-term development of the map are shown to result in tilt aftereffects over short timescales in the adult. The model permits simultaneous observation of large numbers of neurons and connections, making it possible to relate high-level phenomena to low-level events, which is difficult to do experimentally. The results give detailed computational support for the long-standing conjecture that the direct tilt aftereffect arises from adaptive lateral interactions between feature detectors. They also make a new prediction that the indirect effect results from the normalization of synaptic efficacies during this process. The model thus provides a unified computational explanation of self-organization and both the direct and indirect tilt aftereffect in the primary visual cortex.

Exposure apparatus, and device manufacturing method

Abstract: An exposure apparatus for lithographically transferring a pattern of an original onto a substrate to be exposed includes a first detector for detecting a position of an alignment mark on an exposure shot formed on the substrate, a second detector for detecting a local tilt adjacent to the alignment mark, the position of which is detected by the first detector, and a third detector for detecting a tilt of the exposure shot

In situ, real-time measurement of wing tilt during lateral epitaxial overgrowth of GaN

Abstract: By performing in situ, real-time x-ray diffraction measurements in the metalorganic chemical-vapor deposition environment, we have directly observed the emergence and evolution of wing tilt that occurs during the lateral overgrowth of GaN from stripes patterned in a SiO2 mask. This was done by repeatedly performing line scans through the 1013 peak in the direction perpendicular to the [1010]GaN stripe direction. The wing tilt developed as soon as the wings started forming, and increased slightly thereafter to reach a value of ∼1.19° after 3600 s of growth. Upon cooldown to room temperature, the tilt increased to ∼1.36°, indicating that thermally induced stresses during cooldown have only a small effect on wing tilt. However, changes in mask density, composition, and stress state during early lateral overgrowth must be considered as possible origins of wing tilt.

Dual dimensional shoe sensor and foot pedal operated switch for surgical control

Abstract: A shoe sensor for surgical control which may be used in combination with a surgical footpedal includes a tilt sensor for determining angular movement and a cuff for supporting the tilt sensor on a user's in position for enabling the tilt sensor to determine lateral angle movement of the user's foot. A connector is provided for transfer of tilt sensor output to a surgical apparatus controller. When used in combination with a footpedal, the shoe sensor enables additional control parameters to be inputed to a controller by using tilt motion of a user's foot.

Real-time surveying/earth moving system

Abstract: The present invention includes a method and apparatus which determines the three-dimensional (x, y, z coordinate) position of the receiving position of a GPS antenna on an earth-moving machine or a vehicle, determines (147) the tilt of the machine or vehicle in real time (tilt may vary from point to point), and utilizes this data to calculate the three-dimensional (x, y, z coordinate) position of a point of the earth's surface disposed beneath the machine or vehicle. In a preferred embodiment, the present invention derives and displays the distance between the actual elevation of this point and the desired surface elevation.

The asymptotic regimes of tilted Bianchi II cosmologies

Abstract: In this paper we give, for the first time, a complete description of the dynamics of tilted spatially homogeneous cosmologies of Bianchi type II. The source is assumed to be a perfect fluid with equation of state $p = (\gamma -1) \mu$, where $\gamma$ is a constant. We show that unless the perfect fluid is stiff, the tilt destabilizes the Kasner solutions, leading to a Mixmaster-like initial singularity, with the tilt being dynamically significant. At late times the tilt becomes dynamically negligible unless the equation of state parameter satisfies $\gamma > {10/7}$. We also find that the tilt does not destabilize the flat FL model, with the result that the presence of tilt increases the likelihood of intermediate isotropization.

Haemodynamic effects of increasing angle of head up tilt

Abstract: OBJECTIVE—To investigate the haemodynamic effects of varying the angle of head up tilt. METHODS—20 healthy subjects (12 female, eight male; mean (SD) age 33.6 (8.4) years) underwent head up tilt for five minutes to each of four angles of tilt in random order, with a five minute rest period at the horizontal between each angle. Forearm blood flow was measured using intermittent occlusion mercury strain gauge plethysmography at two and five minutes. Subjects underwent continuous monitoring of heart rate, systolic blood pressure (SBP), and diastolic blood pressure (DBP) by Finapres and cardiac output and stroke volume by impedance cardiography. Each variable was measured at two and five minutes, averaged over the period of blood flow measurement. RESULTS—Every haemodynamic variable at each angle was significantly different from supine values. Head up tilt produced progressive increases in heart rate (11-21%), SBP (12-21%), and DBP (20-33%) with increasing tilt angle. However, although 45° produced significantly less haemodynamic effect, there were no significant differences for angles between 60° and 90°. Cardiac output fell on head up tilt by 17-20% and stroke volume by 28-34%, but increasing tilt angle produced no significant additional reduction in cardiac output and stroke volume because of increases in heart rate and vasoconstriction. CONCLUSIONS—Angles < 60° produce significantly less haemodynamic effects than steeper angles. Increasing tilt angle beyond 60° produces no apparent additional effect on cardiac output or sympathetic tone. Increasing tilt angle beyond 60° confers no additional orthostatic stress and may not affect the sensitivity and specificity of head up tilt testing as previously thought. Sixty degrees of tilt is a more practical angle for support of a syncopal patient and is recommended. Keywords: head up tilt test; vasovagal syncope; thoracic impedance

Tilt measurement sensor

Abstract: The paper presents a tilt transducer with ferrofluid, being dedicated to measure little inclination angles in comparison with a horizontal or a vertical plane. The functioning principle, transfer characteristics and utilised electric diagram are submitted.

Tilt angle measurement of low molar mass organosiloxane liquid crystals

Abstract: In this paper we present a modified ‘rotating analyser’ technique that allows rapid and continuous in situ measurements of the optical tilt angle (θ). Using this technique we will detail the tilt angle behaviour in mono-mesogen (AB) and bi-mesogen (ABA) low molar mass orga- nosiloxanes. The AB type molecules exhibit only the ferroelectric SmC* phase and possess a high tilt angle (42-45°) that is independent of temperature throughout the phase range. The ABA molecules containing three silicon atoms exhibit antiferroelectric SmC*Aphases. The tilt angle behaviour during a field induced SmC*A- SmC* transition has also been investigated.

Determination of Director Distributions in Liquid Crystal Polymer-Films by Means of Generalized Anisotropic Ellipsometry

Abstract: We report on how to achieve and measure director tilt angle distributions θ(z) in cross-linked nematic liquid crystal polymer (LCP) films by means of generalized anisotropic ellipsometry. LCP-alignment is made by linearly photopolymerized (LPP)-photo-alignment of LCP films on single substrates. For the first time arbitrary tilt angle distributions are achieved and experimentally verified. It is shown that not only the birefringence Δn of novel LCP-materials, which exhibit values up to Δn=0.4, but also the tilt distribution θ(z) of the LC director can be varied. θ(z) is shown to be tunable between substrate surface and LCP/air interface over the entire range 90°≥θ≥0°. The control of the tilt distribution in thin LCP-films on single substrates is essential for many applications, for instance in LPP/LCP wide-view films designed to increase the field of view of liquid crystal displays (LCDs).

The role of surface tilt in the operation of pi-cell liquid crystal devices

Abstract: The role of surface tilt in the operation of pi-cells (OCB) is discussed. We show the effect of tilt on the relative stability of the H and V states, the switching characteristics and the domain growth speed. We further study the effects of temperature and cell thickness on the domain growth.

Structure for an optical switch on a silicon on insulator substrate

Abstract: Optical cross-connect systems involve the general concept of a two dimensional array of MEMS tilt mirrors being used to direct light coming from a first optical fiber to a second optical fiber. Each MEMS tilt mirror in the two dimensional array can tilt about two non-colinear axes and is suspended by a plurality of suspension arms attached to a silicon on insulator substrate

Projection system comprising at least two light sources having a unique optical arrangement with respect to at least one spatial light modulator

Abstract: Projection system comprising at least two light sources, a projection lens and a spatial light modulator located between the light sources and the projection lens, which light modulator comprises a plurality of light-deflection devices each provided with an element which is tiltable about a tilt axis. The light sources are arranged with respect to the spatial light modulator in such a way that, in operation, the centers of the light beams coming from the light sources and projected on each element are located on a projection line which extends substantially parallel to the tilt axis of the element.

Differential-tilt rytov parameter monitor for atmospheric turbulence

Abstract: An optical configuration and related analysis techniques are presented that provide a practical method for determining the Rytov parameter based on the difference of variances for the differential image motion (average wavefront gradient or wavefront tilt) between two receiving apertures. The Rytov parameter is the log-amplitude variance predicted by an approximate solution to Maxwell's equations for propagation through media with random index of refraction (Rytov theory). It is a useful metric of the optical effects for extended turbulence propagation and is a leading indicator of the performance limitations of adaptive optical compensation devices not related to the transverse coherence diameter. A time-duplex alternative apparatus and a single source alternative apparatus are also disclosed.

Low voltage micro-mirror array light beam switch

Abstract: A micro-optical light beam switch comprises a MEMS (Micro-Electromechanical Systems) mirror array with packaged CMOS driving circuitry. Each movable mirror is coupled to orthogonal pairs of thin unimorph PZT capacitor actuators about peripheral mirror portions for precise positional accuracy in two dimensions by the application of mirror tilt control voltages of 5 volts or less to the actuators. Each cantilevered actuator is individually controllable, allowing multi-axial movement of each mirror via simple flexible stress reducing hinging tab elements for the precise redirection of an incoming light beam to the appropriate targeted location, such as the direction of optical traffic throughout a fiber optic network.

Experimental system of segmented-mirror active optics

Abstract: In this system, the segmented-mirror consists of three submirrors They are hexagonal with 250 mm diagonal The shape of each submirror is spherical with 3000 mm radius and the departure of each radius from the mean radius is less than 0025 mm A special S-H test device is used for co- focus measurement It includes nine sub-apertures in three groups and each group is for a submirror There are six displacement actuators in this system The based unites of it are flexure hinges The actuator is driven by a stepping motor with ten subdivisions Six capacity displacement sensors are used in this experiment system It is made in Tianjin University A computer is used for data collecting, calculating and controlling A special method for co-focus is developed in our work By using this method the error of co-focus, ie the tilt error of submirror, is less than rms 0035 arcseconds The methods of calibration and maintaining for co-phase are also introduced in this paper After once calibration, the diffraction limit image can be observed in about 220 mm aperture at (lambda) 650 nm, and it can be maintained about 20 minutes© (2000) COPYRIGHT SPIE--The International Society for Optical Engineering Downloading of the abstract is permitted for personal use only

Sweep lock and tilt latch combination

Abstract: A pair of sweep locks and a corresponding pair of tilt latches are combined and mounted together on an upper rail of a lower sash. The tilt latches and sweep locks are then interactively engaged so that locking the sweep locks latches the tilt latches, and unlocking the sweep locks leaves the tilt latches latched. Unlocked sweep locks allow manual unlatching of tilt latches, and relocking of sweep locks automatically relatches tilt latches.

Method and device for optically crossconnecting optical signals using tilting mirror mems with drift monitoring feature

Abstract: A device and method for detecting rotational drift of mirror elements in a MEMS tilt mirror array used in an optical crossconnect. The optical crossconnect directs optical signals from an input fiber to an output fiber along an optical path by rotatably positioning mirror elements in desired positions. A monitoring device disposed outside of the optical path is used to obtain images of the MEMS array or to transmit and receive a test signal through the crossconnect for detecting the presence of mirror element drift.