Andrew F. Kurtz

The family window: the design and evaluation of a domestic media space

Families have a strong need to connect with their loved ones over distance. However, most technologies do not provide the same feelings of connectedness that one feels from seeing remote family members. Hence our goal was to understand if a video connection, in the form of a media space, could help families feel more connected and what design factors would be critical for its success. To answer this, we designed a video media space called the Family Window and deployed it within the homes of two families for eight months and four families for five weeks. Our results show that always-on video can lead to an increase in feelings of connectedness by providing availability awareness and opportunities for sharing everyday life. However usage and value of such media spaces hinges on close-knit relationships and control over ones autonomy.

Design of a laser printer using a laser array and beam homogenizer

A novel technique for homogenizing the multitude of beams emanating from a laser diode array is described, as it related to use as an illumination system in a laser printer. This illumination system was required to efficiently transform the multiple beams from a laser array into a single line of uniform light, incident upon a spatial light modulator array, without a loss of brightness. The importance of the laser diode source properties, including both spatial coherence and source Lagrange, will be considered relative to their impact on the system design. The design of the beam shaping optics, including the beam combiner optics and the flys eye integrator assembly, will also be discussed. The implementation of this illumination system in a laser printer employing a modulator array will be discussed, including issues of alignment, component properties, and the results obtained during system integration.

Design Improvements for Motion Picture Film Projectors

This paper describes improvements developed for motion picture film projectors, in particular, new designs for the intermittent, or Geneva mechanism, and for a Universal lamp house. These new designs are intended to improve the quality of the overall screen image as well as light efficiency and uniformity, resulting in significant increases in screen luminance.

25.4: A Laser-Based Digital Cinema Projector

A fully functional DCI capable prototype Laser Digital Cinema Projector has been developed by Eastman Kodak Company using an innovative optical architecture. The prototype demonstrates the potential of the long life and lower operational costs of lasers while minimizing the incremental costs to manufacture. The projector provides over 10,000:1 contrast ratio, an increased color gamut, and an integrated 3D capability that is significantly brighter than is common today in cinema. These attributes are delivered while addressing the impact of laser speckle, eye safety, and other potential impediments to commercialization.

12.1: Digital Cinema Projection with R-LCOS Displays

A digital cinema projector developed by Eastman Kodak Company, utilizing three JVC QXGA liquid crystal displays (LCDs), and providing 12,000 lumens, 2,000:1 contrast, and 3 Mpixel resolution, is described. This system, which has a novel optical configuration, wire grid polarizers and polarization compensators, provides high contrast at low F#, a large color gamut, and minimal stress birefringence at high power.

Optical scanning system for a CCD telecine for HDTV

Motion picture film, as a major source of program material for television, is transferred to the video domain using a telecine. A high performance CCD telecine, operating at real time frame rates, has been developed for high definition television. The optical system for this telecine utilizes a feedback stabilized xenon arc lamp, pre-gate optical and spectral signal balancing, a diffuse illumination system, an apochromatic projection lens, a full resolution CCD luminance sensor, and a half resolution RGB trilinear CCD sensor.

Lens design with reduced sensitivity to thermally induced stress birefringence

In optical systems required to maintain the polarization states of the transiting light, mechanically induced stress birefringence can degrade performance, at least locally altering polarization phase and ultimately reducing polarization contrast. Although thermally induced stress birefringence can cause similar problems in imaging systems bearing high optical flux, appropriate design approaches to resolve this problem have been lacking. This paper first develops criteria to select optical glasses with reduced sensitivity to thermally induced stress birefringence. The design of projection lenses using the resulting thermal stress desensitized reduced glass list is then discussed, as is the application of such lenses in laser projection systems.

An LCOS-based digital-cinema projector

— A digital cinema projector that utilizes three JVC QXGALCDs, and provides 12,000 lumens, 2000:1 contrast, and 3-Mpixel resolution was developed. This system, which was described in a prior paper (see Ref. 10), has a novel optical configuration based on the use of intermediate imaging optics and wire-grid polarizers and is described in greater detail in this paper. The polarization optics, including the polarization compensators, contribute to a system that provides high contrast at a low f/#, with a wide color gamut and minimal color shading at high power.

Gaussian beam apodization and application in a laser printer

A novel technique for controlling the beam width of a single-mode laser beam by Gaussian apodization is discussed. Although, beam truncation is often used to compensate for the typical variations in laser diode beam divergence, such truncation imparts side lobes to the outgoing beam. Gaussian apodization or attentuation of a laser beam provides controlled beam truncation, thereby producing a clean Gaussian beam without side lobes. Typically then, the magnitude of the allowable residual beam divergence variation will be determined by the system light efficiency requirements. However, use of a Gaussian apodizer provides beam divergence control without the use of a complicated zoom system. The implementation of this concept in a prototype flying spot laser print is also discussed, with respect to the impact on the system design and other beam shaping optics, the properties of the prototype Gaussian apodizer, and the results observed during system integration.

Automated videography for residential communications

The current widespread use of webcams for personal video communication over the Internet suggests that opportunities exist to develop video communications systems optimized for domestic use. We discuss both prior and existing technologies, and the results of user studies that indicate potential needs and expectations for people relative to personal video communications. In particular, users anticipate an easily used, high image quality video system, which enables multitasking communications during the course of real-world activities and provides appropriate privacy controls. To address these needs, we propose a potential approach premised on automated capture of user activity. We then describe a method that adapts cinematography principles, with a dual-camera videography system, to automatically control image capture relative to user activity, using semantic or activity-based cues to determine user position and motion. In particular, we discuss an approach to automatically manage shot framing, shot selection, and shot transitions, with respect to one or more local users engaged in real-time, unscripted events, while transmitting the resulting video to a remote viewer. The goal is to tightly frame subjects (to provide more detail), while minimizing subject loss and repeated abrupt shot framing changes in the images as perceived by a remote viewer. We also discuss some aspects of the system and related technologies that we have experimented with thus far. In summary, the method enables users to participate in interactive video-mediated communications while engaged in other activities.