How Computers Find Your Pupil Even With Glare
This patent describes a computer method to accurately find the outline of a person's eye pupil by using radial search lines and handling bright reflections differently from clear areas.
Original patent title: “Recording medium storing computer program for pupil detection, information processing apparatus, and pupil detecting method”
This patent describes a computer method to accurately find the outline of a person's eye pupil by using radial search lines and handling bright reflections differently from clear areas. Granted to Fujitsu in 2020 with 21 claims and 1 forward citation, and it is expected to expire in 2038.
Key facts
Coverage
What does this patent actually cover?
The patent describes a method for a computer to precisely locate a user's pupil from an eye image. First, it identifies the general "eye area" and any "bright spot areas" within it, which are often reflections (ClaimclaimA numbered sentence at the end of a patent that legally defines what the inventor owns. The most important section.Read more → 1). It then sets a central "reference point" within the assumed pupil and draws many "first search lines" extending outwards like spokes on a wheel. For lines that hit a bright spot (a "second search line"), the system figures out how much the bright spot overlaps the pupil by checking brightness around the bright spot's circumference. This helps it set a specific "search range" to find a "first point" on the pupil's edge. For lines that don't hit a bright spot (a "third search line"), it directly finds a "second point" on the pupil's edge. Finally, it uses both the first and second points to map out the entire pupil. For example, if a camera needs to track where a user is looking, this method helps it find the pupil accurately even if there's a camera flash reflection.
The gap
What does this patent NOT cover?
- Pupil detection methods that do not use radial search lines extending from a central reference point.
- Systems that do not differentiate between search lines passing through bright spots and those that do not.
- Methods that do not determine a "degree of overlapping" for bright spots or set a "search range" based on it.
- Pupil detection based solely on overall brightness thresholds without specific bright spot handling logic.
- Methods that rely purely on machine learning models without the explicit radial search line and bright spot differentiation steps.
These exclusions are unique to PatentBrief — derived from the actual claim language, not patent-office boilerplate.
What made this novel
The noveltynoveltyThe requirement that an invention be different from anything publicly known before its priority date.Read more → lies in intelligently combining two different strategies for finding the pupil contour: one for areas obscured by bright reflections (using "degree of overlapping" and a "search range") and another for clear areas, allowing for robust detection despite glare.
The Patent Drawing
Schematic visualization of the patent's claim structure. Hand-drawn diagrams in progress for each landmark patent.
Where you've seen this
Real-world examples
Eye-tracking systems in VR/AR headsets
Driver monitoring systems in cars
Accessibility tools for computer control
Gaze estimation for user interfaces
Why it matters
The bigger picture
Accurate pupil detection is critical for eye-tracking technologies used in various fields. This patent offers a way to improve the reliability of pupil detection, especially in challenging lighting conditions where reflections might otherwise confuse a system. This can lead to more precise user interaction in virtual reality, augmented reality, and accessibility tools.
Filed
May 25, 2018
Granted
June 23, 2020
Market context
Who's building on this
Companies in this space
Companies like Tobii, Pupil Labs, and Meta (for their VR headsets) are actively developing and integrating advanced eye-tracking technologies. Fujitsu, the assigneeassigneeThe entity that owns the patent — usually the inventor's employer or a company.Read more →, continues to research and apply computer vision in various products, including those that might benefit from robust pupil detection.
Market impact
This type of technology contributes to the increasing accuracy and reliability of eye-tracking systems in various devices. It enables better user experience in devices like VR headsets by making gaze tracking more robust to environmental challenges, and supports the development of more sophisticated driver assistance and accessibility features in the automotive and assistive technology sectors.
Claim 1 — Plain English
What this patent covers
The patent describes a method for a computer to precisely locate a user's pupil from an eye image. First, it identifies the general "eye area" and any "bright spot areas" within it, which are often reflections (Claim 1). It then sets a central "reference point" within the assumed pupil and draws many "first search lines" extending outwards like spokes on a wheel. For lines that hit a bright spot (a "second search line"), the system figures out how much the bright spot overlaps the pupil by checking brightness around the bright spot's circumference. This helps it set a specific "search range" to find a "first point" on the pupil's edge. For lines that don't hit a bright spot (a "third search line"), it directly finds a "second point" on the pupil's edge. Finally, it uses both the first and second points to map out the entire pupil. For example, if a camera needs to track where a user is looking, this method helps it find the pupil accurately even if there's a camera flash reflection.
The clever bit
The novelty lies in intelligently combining two different strategies for finding the pupil contour: one for areas obscured by bright reflections (using "degree of overlapping" and a "search range") and another for clear areas, allowing for robust detection despite glare.
What it does not cover
- Pupil detection methods that do not use radial search lines extending from a central reference point.
- Systems that do not differentiate between search lines passing through bright spots and those that do not.
- Methods that do not determine a "degree of overlapping" for bright spots or set a "search range" based on it.
- Pupil detection based solely on overall brightness thresholds without specific bright spot handling logic.
- Methods that rely purely on machine learning models without the explicit radial search line and bright spot differentiation steps.
Patent timeline
Application submitted to the patent office
Application published, typically 18 months after filing
Patent officially issued
Patent enters public domain
PatentBrief Score
Impact Score
Early stage
Citation count
6/40
Early citations
Claim breadth
14/20
Broad claimsclaimsThe numbered statements at the end of a patent that legally define what the inventor owns.Read more →
Recency
10/20
Granted 5–10 years ago
Assignee scale
0/20
Independent or smaller assigneeassigneeThe entity that owns the patent — usually the inventor's employer or a company.Read more →
PatentBrief Impact Score — based on citation count, claim breadth, recency, and assignee scale. Not a legal assessment.
Heuristic Value Estimate
What this patent might be worth
$78K – $250K
Midpoint $156K · 11.9 yr remaining · industry ×1.6
Heuristic only — blends forward/backward citation counts, claim scope, time remaining, litigation history, and CPC-derived industry baseline. Real valuations need a professional appraisal.
The original legal language
Original claims
21 claims as filed with the patent office.
Concepts involved
Citations
Patent lineage
Cite this patent
Nakayama, O., & Ishii, D. (2020). How Computers Find Your Pupil Even With Glare (U.S. Patent No. 10,692,210). U.S. Patent and Trademark Office. https://patentbrief.org/patent/us/10692210/recording-medium-storing-computer-program-for-pupil-detection-information-proces
Auto-generated from the patent record. Double-check author order and the issue date against the official USPTO document before submitting.
Embed
Add this patent to your site
Drop this plain-English patent card into any blog post or article — free, no signup. It always links back to the full breakdown here.
<div data-patentlens-widget data-patent-number="US10692210"></div> <script src="https://patentbrief.org/embed.js" async></script>
Stay in the loop
Get a weekly digest of new patents.
One email per week. No spam. Unsubscribe anytime.
Keep exploring
Related patents you should know
US 4683195 · 1987
How to Make Billions of Copies of a DNA Segment
This patent describes the Polymerase Chain Reaction (PCR), a method to rapidly create many copies of a specific piece of DNA or RNA, enabling its detection and analysis.
Cetus Corp
US 8697359 · 2014
How to Edit Genes in Human Cells Using an Engineered CRISPR System
This patent describes an engineered CRISPR-Cas9 system for precisely cutting DNA in eukaryotic cells to change how genes work, opening the door for gene editing in complex organisms.
Massachusetts Institute of Technology
US 7657849 · 2010
How the iPhone's Slide-to-Unlock Gesture Works
Apple's 2010 patent describes unlocking a device by dragging a specific graphical image across the touchscreen along a predefined path, a gesture that became iconic with the original iPhone.
Apple Inc
US 4733665 · 1988
How Doctors Implant a Permanent Stent Using a Balloon
This patent describes the method for placing a permanent, expandable wire mesh tube inside a blood vessel or other body tube using a balloon-tipped catheter to widen it and keep it open.
Expandable Grafts Partnership
US 4965188 · 1990
How to Make Many Copies of a DNA Piece with Heat
This patent describes the Polymerase Chain Reaction (PCR) method, a technique to make millions of copies of a specific DNA segment using a heat-resistant enzyme and repeated temperature changes.
Cetus Corp
US 4235871 · 1980
How to Encapsulate Active Materials in Lipid Bubbles Efficiently
This patent describes a method for trapping biologically active substances inside tiny, multi-layered fat bubbles called liposomes, using a specific water-in-oil emulsion and gel-forming process to improve how much material gets captured.
Individual
Semantically similar
You might also find these interesting
US 7812828 · 2010 · Apple Inc
How Touchscreens Use Math to Recognize Your Fingers
US 20160291760 · Wacom Co
Adjusting Touchscreen Sensitivity Based on Device Tilt Angle
US 7957762 · 2011 · Apple Inc
How Your Phone Knows When It's Against Your Ear
US 7479949 · 2009 · Apple Inc
How Touchscreens Understand Your Finger Swipes and Scrolls
More to explore
More in Consumer Electronics
US 7657849 · 2010 · Apple Inc
How the iPhone's Slide-to-Unlock Gesture Works
US 7479949 · 2009 · Apple Inc
How Touchscreens Understand Your Finger Swipes and Scrolls
US 4528643 · 1985 · FPDC Inc
How Stores Make Custom Products On-Demand with Remote Approval
US 7469381 · 2008 · Apple Inc
How Touchscreens Show and Snap Back When You Scroll Past an Edge
New to patents?
Common Questions
Frequently Asked Questions
What does How Computers Find Your Pupil Even With Glare cover?
This patent describes a computer method to accurately find the outline of a person's eye pupil by using radial search lines and handling bright reflections differently from clear areas.
Who owns patent US 10692210?
Fujitsu owns this patent, granted in 2020.
When does this patent expire?
This patent is expected to expire on May 25, 2038, when the invention enters the public domain.
What is patent US 10692210 cited by?
This patent has been cited by 1 later patents that build on its ideas.
What problem does this patent solve?
Accurate pupil detection is critical for eye-tracking technologies used in various fields. This patent offers a way to improve the reliability of pupil detection, especially in challenging lighting conditions where reflections might otherwise confuse a system. This can lead to more precise user interaction in virtual reality, augmented reality, and accessibility tools.
What does this patent NOT cover?
Pupil detection methods that do not use radial search lines extending from a central reference point.
Patent monitoring