Luminescence imaging for sensing and/or authentication

Inventors

Swager, Timothy Manning • Cox, Jason R. • Deans, Robert

Assignees

C2Sense Inc

Abstract

Compositions, articles, systems, and methods for sensing and/or authentication using luminescence imaging are generally provided. In some embodiments, an article (or packaging material of an article) is associated with an emissive material comprising an emissive species (e.g., a luminescent species). In some cases, the emissive species has an emission lifetime of at least 10 nanoseconds (ns). In some cases, a characteristic of an article (e.g., identity, authenticity, age, quality, purity) may be determined by obtaining an image (or series of images) comprising time-dependent information related to an emissive species. In certain instances, for example, the emission lifetime of an emissive species may be determined from an image (or series of images). Since the emission lifetime of an emissive species may be modified by a number of factors, including but not limited to binding or proximity to other molecules (e.g., water, oxygen, carbon monoxide), temperature, pH, and radiation exposure, the measured length of the emission lifetime (e.g., the observed emission lifetime, the emission time period) may provide information regarding a characteristic of an associated article. In some instances, an emissive material comprising one or more emissive species may be used to identify and/or authenticate an associated article.

Core Innovation

The disclosure provides luminescence imaging for sensing and authentication using an emissive species that produces a detectable non-steady-state emission during an emission time period. The emission time period is extracted from images, and the emission time period includes at least 10 nanoseconds. Excitation and capture enable the non-steady-state emission to be resolved into time-dependent image regions within a single captured image.

A system is described in which an article-associated emissive/chemical tag is associated with an environment-dependent emission lifetime and/or emission profile. Emission lifetime varies with binding or proximity to molecules including water, oxygen, and carbon monoxide, temperature, pH, radiation exposure, quenching, and other environmental conditions. The emission lifetime and/or an emission profile can be extracted from images, including single images constructed from portions captured at different times via rolling-shutter imaging.

The disclosure characterizes excitation and imaging concepts including pulsed or modulated excitation and broadband or white light excitation without multiple filters, together with rolling-shutter temporal multiplexing. It provides application contexts for identity, authenticity, and quality assessment and detecting stimuli, including diagnostics and security. The emissive materials are described as non-steady-state emissive species such as TADF molecules or exciplexes and phosphors, heavy-atom or organometallic species including lanthanides and actinides, with tunability for lifetime and wavelength-based encoding.

Claims Coverage

The partial content includes four independent claims that collectively cover a rolling-shutter luminescence imaging system that converts time-varying non-steady-state emission into a single image with temporally partitioned portions. Across the independent claims, at least four main inventive features are explicitly recited: non-steady-state emission during an emission time period of at least 10 nanoseconds, excitation using electromagnetic radiation in a wavelength range where recited, rolling-shutter sequential readout that maps different emission-time portions to different image portions, and association of differences between image portions with identification of a characteristic of a chemical tag where specified.

Across the independent claims, the inventive coverage centers on exciting or exposing an emissive species to produce detectable non-steady-state emission lasting at least 10 nanoseconds, capturing the time-varying emission with a rolling shutter by sequentially reading pixel rows or columns to map different emission-time portions into different portions of a single image or frame, and associating differences between those image portions with identification of a characteristic of a chemical tag.

Stated Advantages

Documented Applications