Calibration of a multiview display with a tilted parallax barrier for reduction of nonlinear extrinsic crosstalk.

Multiview displays, which are capable of displaying different view-images for viewers at different positions, can suffer from undesirable view-image mixing, called crosstalk. In this paper, we propose a method to minimize a class of crosstalk that occurs due to misalignment of flat panel displays and parallax barriers that constitute multiview displays. More specifically, our method is aimed at cases where flat panel displays and parallax barriers are non-parallel. First, we introduce our framework, which associates homography matrices to sets of pixels visible through parallax barriers. Then, we propose an iterative method for finding pixels that are visible for a view-point. By using a stripe test pattern, the homography matrix that corresponds to a set of visible pixels can be found by monitoring the deformation of the stripe test pattern. Last, we experimentally check the validity of the iterative method and demonstrate that the proposed method successfully corrects the geometric distortion of a 3D image.

Iterative calibration of a multiview 3D display with linear extrinsic crosstalk using camera feedback.

In this paper, we propose a multiview 3D display calibration algorithm that compensates for misalignment between constituent layers. To minimize distortion of the 3D image due to misalignment, we employ an iterative algorithm using camera feedback. We first establish a mathematical model for the multiview display and predict distortion of a test image pattern due to misalignment. Then, we define two characteristic features of the feedback camera image that indicate the status of the alignment. Based on the mathematical model, we design a compensation algorithm that consists of cascaded one-dimensional root-finding blocks for two-dimensional optimization. Finally, we experimentally verify the image distortion model, convergence of the iterative algorithm, and image quality improvement. The accuracy of the proposed algorithm exceeds the required accuracy for linear extrinsic crosstalk compensation.

Perceptual Space of Superimposed Dual-Frequency Vibrations in the Hands.

The use of distinguishable complex vibrations that have multiple spectral components can improve the transfer of information by vibrotactile interfaces. We investigated the qualitative characteristics of dual-frequency vibrations as the simplest complex vibrations compared to single-frequency vibrations. Two psychophysical experiments were conducted to elucidate the perceptual characteristics of these vibrations by measuring the perceptual distances among single-frequency and dual-frequency vibrations. The perceptual distances of dual-frequency vibrations between their two frequency components along their relative intensity ratio were measured in Experiment I. The estimated perceptual spaces for three frequency conditions showed non-linear perceptual differences between the dual-frequency and single-frequency vibrations. A perceptual space was estimated from the measured perceptual distances among ten dual-frequency compositions and five single-frequency vibrations in Experiment II. The effect of the component frequency and the frequency ratio was revealed in the perceptual space. In a percept of dual-frequency vibration, the lower frequency component showed a dominant effect. Additionally, the perceptual difference among single-frequency and dual-frequency vibrations were increased with a low relative difference between two frequencies of a dual-frequency vibration. These results are expected to provide a fundamental understanding about the perception of complex vibrations to enrich the transfer of information using vibrotactile stimuli.

Discriminant and criterion-related validity of a relative deprivation scale in a merger and acquisition context.

This study examined the discriminant and criterion-related validity of the Relative Deprivation Scale. The data were collected from 151 Korean employees who had recently experienced a merger and acquisition. The results of confirmatory factor analysis revealed that the two dimensions of relative deprivation (egoistic and fraternal relative deprivation) are clearly distinguishable from other conceptually related variables, such as negative affectivity, resistance to change, overall job dissatisfaction, and distributive justice. In addition, egoistic relative deprivation made a unique incremental contribution to explaining employee turnover intention beyond the contribution of conceptually related variables, while fraternal relative deprivation did not.

Maximization of acoustic energy difference between two spaces.

There has recently been an increasing interest in the generation of a sound field that is audible in one spatial region and inaudible in an adjacent region. The method proposed here ensures the control of the amplitude and phase of multiple acoustic sources in order to maximize the acoustic energy difference between two adjacent regions while also ensuring that evenly distributed source strengths are used. The performance of the method proposed is evaluated by computer simulations and experiments with real loudspeaker arrays in the shape of a circle and a sphere. The proposed method gives an improvement in the efficiency of radiation into the space in which the sound should be audible, while maintaining the acoustic pressure difference between two acoustic spaces. This is shown to give an improvement of performance compared to the contrast control method previously proposed.