Optical Fiber, Optical Fiber Preparation Method, and Optical Fiber Amplifier
US-2025316945-A1 · Oct 9, 2025 · US
doped with phosphorus
doped with phosphorus · Cooperative Patent Classification (CPC)
Chemical and metallurgical processes, compounds, and materials.
Related technology areas
Mapped technology topics for this CPC code.
| Metric | Value |
|---|---|
| CPC code | C03B2201/28 |
| Official title | doped with phosphorus |
| Display label | doped with phosphorus |
| Total patents | 57 |
Filing trend
Year-over-year patent counts classified under this CPC code.
Filing activity over the last five years is declining.
| Year | Patents |
|---|---|
| 2015 | 10 |
| 2016 | 5 |
| 2017 | 4 |
| 2018 | 3 |
| 2019 | 5 |
| 2020 | 6 |
| 2021 | 6 |
| 2022 | 3 |
| 2023 | 9 |
| 2024 | 3 |
| 2025 | 3 |
Representative patents
Representative publications under this CPC code from precomputed stats, or recent filings when stats are unavailable.
Silica glass body manufacturing method and heating device
US-2025091932-A1 · Mar 20, 2025 · US
Reducing light-induced loss in optical fibre
US-2025052946-A1 · Feb 13, 2025 · US
Reducing light-induced loss in optical fibre
US-12135453-B2 · Nov 5, 2024 · US
Cleaning step to remove metals or metal oxides from porous glass body
US-2024360024-A1 · Oct 31, 2024 · US
Radiation-resistant laser optical fiber preform core rod and preparation method therefor
US-12001052-B2 · Jun 4, 2024 · US
Optical fiber with variable absorption
US-11808970-B2 · Nov 7, 2023 · US
Photodarkening-resistant ytterbium-doped quartz optical fiber and preparation method therefor
US-11780768-B2 · Oct 10, 2023 · US
Reducing light-induced loss in optical fibre
US-2023305222-A1 · Sep 28, 2023 · US
Optical fiber
US-11740404-B2 · Aug 29, 2023 · US
Reducing light-induced loss in optical fibre
US-11698484-B2 · Jul 11, 2023 · US
Burner design for particle generation
US-11667558-B2 · Jun 6, 2023 · US
Manufacturing method for optical fiber and manufacturing apparatus for optical fiber
US-11667560-B2 · Jun 6, 2023 · US
Optical fibers and method of making the same
US-2023167002-A1 · Jun 1, 2023 · US
System and method for optical fiber preform preparation via high-surface-area coating
US-11655183-B2 · May 23, 2023 · US
Radiation-resistant laser optical fiber preform core rod and preparation method therefor
US-2022342147-A1 · Oct 27, 2022 · US
Process of fabrication of Erbium and Ytterbium-co-doped multi-elements silica glass based cladding-pumped fiber
US-11407671-B2 · Aug 9, 2022 · US
Optical fiber with variable absorption
US-2022077643-A1 · Mar 10, 2022 · US
System and method for optical fiber preform preparation via high-surface-area coating
US-2021387903-A1 · Dec 16, 2021 · US
Method and apparatus for reproducibly producing a preform for glass fiber manufacture
US-2021309558-A1 · Oct 7, 2021 · US
Frequently asked questions
Answers are generated from the same data shown on this page.
- What is CPC C03B2201/28?
- CPC C03B2201/28 is the Cooperative Patent Classification code for “doped with phosphorus.”
- How many patents are filed under CPC C03B2201/28 (doped with phosphorus)?
- Our database includes 57 publications tagged with this CPC code.
- Is patent activity under CPC C03B2201/28 growing?
- Publication counts under this code: 3 in 2024 vs 3 in 2025 (latest complete years).