Micro-electronic power supply for electrochromic eyewear
US5900720A · kind A · utility
Inventors
Key dates
| Filing date | Oct 2, 1997 |
| Grant date | May 4, 1999 |
| Priority date | — |
| Expiry date | Oct 2, 2017 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02C7/101
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A power and control system for micro-electronics is described, as for lightweight, battery-powered electrochromic (EC) eyewear. Preferably such system includes a primary, lithium-type cell and a secondary, sealed lead acid-type cell in a hybrid, power-sharing configuration capable of supplying the low-energy, high-current (pulse) drain requirements of microelectronics, e.g. a switchable EC lens. A switch-mode power supply controller manages the power-sharing load on the hybrid battery system such that the secondary cell is charged by the primary cell. The system is capable of meeting short-term pulse drain requirements of switching EC lenses from clear to fully darkened at an acceptably fast rate and long-term operating life requirements of approximately 1500 cycles. The invented lead acid-type battery preferably is elongate, of uniform, right-rectangular cross section and provides over 20 mA-hours' capacity and the invented lithium-type battery preferably also is elongate, of uniform, right-rectangular cross section and provides over 180 mA-hours' capacity, all in a tiny volume compatible with one or more volume-restricted spaces. Preferably, the lithium-type and lead acid-type ba…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.