University of Michigan

Pei-Cheng Ku

Garen V Vartanian

Kwoon Y Wong

Scott A Almburg

Kunook Chung

Max Shtein

Brandon Demory

Yin-Ting Yeh

Jingyang Sui

A light source and a method of generating a light using the light source is disclosed. The light source is configured to produce a plurality of distinct colors in generating the light, one of the distinct colors falling within a blue spectral light band. A light controller modulates the spectral light produced by the plurality of distinct colors. The modulation provides melanopsin contrast in order to increase melanopsin responsiveness of a subject exposed to the generated light and maintains the color temperature, color quality, and color constancy experienced by the subject in a lit viewing environment within an acceptable range.

Temporally modulated multi-LED for enhanced subconscious physiological responses

A device includes a substrate and a set of force sensors supported by the substrate. Each force sensor includes a pillar extending outward from the substrate, each pillar comprising a stack of semiconductor layers, the stack of semiconductor layers being configured to emit light upon biasing of the stack of semiconductor layers, and post disposed along only a portion of a perimeter of the pillar such that, taken together, the pillar and the post have an asymmetrical cross-sectional shape. Each pillar has a cross-section elongated along an axis. An orientation of the axis, and a peripheral position of the portion of the perimeter at which the post is disposed, differ across the set of force sensors such that a variation in light emitted by the stack of semiconductor layers of one or more of the force sensors is indicative of a direction of a shear force applied to the set of force sensors.

Light-based tactile sensing with directional sensitivity

Additive color mixing across the visible spectrum was demonstrated from a light emitting diode (LED) pixel comprising of red, green, and blue subpixels monolithically integrated and enabled by local strain engineering. The device was fabricated using a top-down approach on a metal-organic chemical vapor deposition-grown sample consisting of a typical LED epitaxial stack. The three color subpixels were defined in a single lithographic step. The device was characterized for its electrical properties and emission spectra under an uncooled condition, which is desirable in practical applications. The color mixing was controlled by pulse width modulation and the degree of color control was also characterized.

Color mixing monolithically integrated light-emitting diode pixels

A solid state light source comprising a light pump outputting light energy; a waveguide optically coupled to the light pump source for receiving the light energy; and a down-converter for converting the light energy from the waveguide to a lesser light energy.

Solid state light source based on hybrid waveguide-down-converter-diffuser

An optical memory includes an array of optical material and a beam scanning device. The optical material assumes first and second states, and incident light causes the optical material to transition from the first state to the second state. The beam scanning device selectively directs a received optical data signal across the array of optical material.

Growing community of inventors

Ann Arbor, MI, United States of America

Pei-Cheng Ku