IP Library Granted Patent US 12,354,047
Granted Patent B2
US 12,354,047 · App. 18/279,179 · Granted Jul 8, 2025

Estimation device, estimation method, and estimation program

Inventors: Jumpei Yamashita (Musashino, JP); Akira Kataoka (Musashino, JP); Hidetaka Koya (Musashino, JP)
Assignee: Nippon Telegraph and Telephone Corporation
G06Q10/06398G06T7/254G06T7/62G06T2207/30201
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Quick Facts
Patent No.
US 12,354,047
App. No.
18/279,179
Granted
Jul 8, 2025
Kind
B2
Abstract

An estimation device includes processing circuitry configured to acquire time-series data of a pupil diameter during work of a subject of work performance estimation, smooth the time-series data of the pupil diameter of the subject by a first time window, smooth the time-series data of the pupil diameter by a second time window that is a time window larger than the first time window, calculate a difference between time-series data of the pupil diameter smoothed by the first time window and time-series data of the pupil diameter smoothed by the second time window, and estimate a level of work performance of the subject based on a magnitude of the difference between the time-series data of the pupil diameter smoothed by the first time window and the time-series data of the pupil diameter smoothed by the second time window, and output a result of the estimation.

Claims (31)

1. An estimation device comprising:

processing circuitry configured to:

acquire time-series data of a pupil diameter during work of a subject of work performance estimation;

smooth the time-series data of the pupil diameter of the subject by a first time window;

smooth the time-series data of the pupil diameter by a second time window that is a time window larger than the first time window;

calculate a difference between time-series data of the pupil diameter smoothed by the first time window and time-series data of the pupil diameter smoothed by the second time window; and

estimate a level of work performance of the subject based on a magnitude of the difference between the time-series data of the pupil diameter smoothed by the first time window and the time-series data of the pupil diameter smoothed by the second time window, and output a result of the estimation.

2. The estimation device according to claim 1 ,

wherein the processing circuitry is further configured to

estimate that the larger the difference between the time-series data of the pupil diameter smoothed by the first time window and the time-series data of the pupil diameter smoothed by the second time window, the lower the work performance of the subject.

3. The estimation device according to claim 1 ,

wherein the processing circuitry is further configured to estimate that the smaller the difference between the time-series data of the pupil diameter smoothed by the first time window and the time-series data of the pupil diameter smoothed by the second time window, the higher the work performance of the subject.

4. The estimation device according to claim 1 ,

wherein the pupil diameter during work of the subject is a pupil diameter measured by an infrared camera or a visible light camera.

5. The estimation device according to claim 1 , wherein the processing circuitry is further configured to calculates a first value that is an average value of absolute values of values obtained by first differentiating the time-series data of the pupil diameter smoothed by the first time window, calculate a second value that is an average value of absolute values of values obtained by first differentiating the time-series data of the pupil diameter smoothed by the second time window, and set an absolute value of a difference between the first value and the second value as the difference.

6. The estimation device according to claim 1 ,

wherein the processing circuitry is further configured to

set an average value of absolute values of differences between the time-series data of the pupil diameter smoothed by the first time window and the time-series data of the pupil diameter smoothed by the second time window at each time as the difference.

7. The estimation device according to claim 1 , wherein the processing circuitry is further configured to exclude, from the time-series data of the pupil diameter, time-series data of the pupil diameter in a period in which a value of the pupil diameter is equal to or less than a predetermined threshold.

8. An estimation method performed by an estimation device, the estimation method comprising:

acquiring time-series data of a pupil diameter during work of a subject of work performance estimation;

smoothing the time-series data of the pupil diameter of the subject by a first time window;

smoothing the time-series data of the pupil diameter by a second time window that is a time window larger than the first time window;

calculating a difference between time-series data of the pupil diameter smoothed by the first time window and time-series data of the pupil diameter smoothed by the second time window; and

estimating a level of work performance of the subject based on a magnitude of the difference between the time-series data of the pupil diameter smoothed by the first time window and the time-series data of the pupil diameter smoothed by the second time window, and outputs a result of the estimation.

9. A non-transitory computer-readable recording medium storing therein an estimation program that causes a computer to execute a process comprising:

acquiring time-series data of a pupil diameter during work of a subject of work performance estimation;

smoothing the time-series data of the pupil diameter of the subject by a first time window;

smoothing the time-series data of the pupil diameter by a second time window that is a time window larger than the first time window;

calculating a difference between time-series data of the pupil diameter smoothed by the first time window and time-series data of the pupil diameter smoothed by the second time window; and

estimating a level of work performance of the subject based on a magnitude of the difference between the time-series data of the pupil diameter smoothed by the first time window and the time-series data of the pupil diameter smoothed by the second time window, and outputs a result of the estimation.

Assignments (2)
CHANGE OF NAME Recorded Dec 5, 2025
From: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
To: NTT, INC.
Reel/Frame 073861/0410 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Oct 26, 2023
From: YAMASHITA, JUMPEI; KATAOKA, AKIRA; KOYA, HIDETAKA
To: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
Reel/Frame 065359/0932 →
Continuity (1)
Related Publication 20240135300A1 · Apr 25, 2024
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