Invalidity dossier
US 4897771
Reflector and light system
Current assignee: Solid State Opto Ltd
Added 9/23/2026, 2:39:41 PM
Active provider: DeepSeek · deepseek-flash
Patent summary
Title, assignee, inventors, filing/issue dates, abstract, and a plain-language overview of the claims.
Patent Overview — US4897771A
Title: Reflector and light system
Patent number: US4897771A
Application number: US07/125,323
Inventor: Jeffrey R. Parker
Original assignee: Lumitex Inc.
Priority/filing date: 1987-11-24
Publication (grant) date: 1990-01-30
Status as listed: Expired – Lifetime
Purpose: The patent addresses inefficient light collection and focusing. As stated in the supplied text, prior systems suffered because "the focal point for the forwardly facing reflector is within the reflector system itself," and a forwardly facing reflector "reflects the light as a parallel beam, which makes it difficult to focus the light on a relatively tight target outside the reflector," with light reflected back through the source blocking "a large percentage of the light before it reaches the target."
Plain-language scope: The disclosed system includes a rearwardly facing collecting reflector that gathers light emitted from a source at its focal point, plus a forwardly facing back reflector that receives the collected light and redirects it back through the collecting reflector onto a target outside the assembly. In one form, the source is a lens-end incandescent bulb projecting a cone through an axial opening in the smaller end of the collecting reflector. Light not directly projected is emitted radially as a conical section (rays d and x) and reflected onto the back reflector, then re-reflected back through the opening and focused on the target, "preferably substantially without striking the light source or restriking the collecting reflector." The collecting reflector may be an ellipsoidal section and the back reflector a flat circular disc with a central hole, optionally axially adjustable for focusing and vented for cooling. Alternatives in the excerpt include parabolic collecting and back reflectors, use of a light pipe, two targets, and a light emitting diode cast with the reflectors as a single modular unit.
Source: https://patents.google.com/patent/[US4897771](/patent/US4897771)/en
What the excerpt does not establish: It is an excerpt only; the full claims, the complete specification, and all drawing details are not provided. It does not establish claim scope, the complete list of embodiments, prior-art references, validity, or ownership history.
Generated 10/1/2026, 9:52:04 PM
Cases on file (0)
Specific litigation cases in our database that name US patent 4897771. The free-form analysis below may also discuss cases beyond this list.
No cases on file mention this patent. Upload a CSV or add a case manually in Admin → Manage litigation cases.
Litigation summary
Past and pending lawsuits — plaintiffs, defendants, jurisdictions, outcomes, and notable rulings.
Proceedings on file (0)
All PTAB activity →AIA trial proceedings (IPR / PGR / CBM) filed at the USPTO Patent Trial and Appeal Board against this patent. Sourced from the USPTO Open Data Portal and refreshed every six hours; each proceeding number deep-links to the PTAB E2E docket.
No PTAB proceedings on file. This patent has not been challenged via IPR, PGR, or CBM. The absence is itself a signal — well-asserted patents eventually attract IPRs. The LLM analysis below may surface filings the ODP feed hasn’t indexed yet.
PTAB challenges
AIA trial proceedings at the USPTO Patent Trial and Appeal Board — IPR, PGR, and CBM. Petitioners, judge panels, claim-level invalidation outcomes from Final Written Decisions, and Federal Circuit appeals. The single most important defensive datapoint after litigation history.
Assignment history
Inventors, original assignee, and the chain of ownership recorded with the USPTO — including the correspondent attorney who recorded each assignment, since shell-LLC chains often share one repeat-player attorney even when the entity names look unrelated. Surfaces NPE / patent-troll patterns: shell-entity transfers, known asserters in the chain, repeat correspondent fingerprints, pre-litigation assignments, and bankruptcy fire-sales.
Prior art
Earlier patents, publications, and products that may anticipate or render the claims unpatentable.
Obviousness
Combinations of prior art that suggest the claimed invention would have been obvious under 35 U.S.C. § 103.
Extensions
Patent term adjustments, term extensions, continuations, divisionals, family members, and expiration dates.
Derivative works
Defensive disclosure: derivative variations of each claim designed to render future incremental improvements obvious or non-novel.