Phase Plate Patents: Who Leads, Where the Gaps Are 2026
- 65.2% concentration at the top. The top 5 of 51 ranked assignees hold 101 of the 155 records in scope — a field with a short, dominant leadership tier.
- Filing cooled from its 2023 peak. Volume ran from 21 records in 2021 to 13 in 2024, a documented -38% over that span, after peaking at 24 records in 2023.
- Optics and biology overlap heavily. C07K peptide claims (47.1% of records) outnumber H01J electron-tube claims (20.6%), showing most filings are biological-sample-side, not instrument-side.
Filing growth compares 2021 (21 records) with 2024 (13) — a three-year span. 2024 is the most recent year we treat as complete: publication lags filing by roughly 18 months, so 2025 onwards are still filling in and any growth rate that ends there would understate the field. Top-5 share is the combined record count of the five largest assignees divided by all 155 records in scope (CR5), not by the ranked leaders only.
What this landscape covers
Phase plates address a specific problem in electron microscopy: unstained, low-contrast biological samples — proteins, viral particles, small macromolecular complexes — produce weak signal under conventional defocus-based phase contrast. A physical or laser-induced phase plate shifts the phase of unscattered electrons relative to scattered ones, sharpening contrast without heavy defocus. This search set combines that instrument-side language with terms tied to practical failure modes: charging drift, alignment stability, and hole-free plate designs, alongside the downstream biological targets these plates are built to image.
The 155 records in scope span 2015 through the 2026-07-31 cut-off. Because publication lags filing by roughly 18 months, the most recent one to two years understate true filing activity and should be read as provisional rather than a genuine slowdown.
Filing trend and technology mix
Two views of the same 155-record set: activity over time, and where records land across IPC subclasses. Because a single record can carry several IPC codes, the subclass shares below sum to more than 100% of records.
Filing trend, 2017-2026
Volume rose to a peak of 24 records in 2023, then eased to 13 in 2024 — a documented -38% from the 2021 level of 21. 2025 and 2026 figures are still filling in as publications catch up to filing dates, so treat the tail as incomplete rather than declining.
IPC subclass composition
C07K (peptides & proteins) leads at 47.1% of the 155 records, ahead of C12N (microorganisms & genetic engineering) at 29.0% and A61K (medicinal preparations) at 22.6%. Instrument-side classes — H01J (electron & discharge tubes) at 20.6% and G02F (optical control & modulation) at 12.9% — sit well behind the biological classes, indicating the corpus is weighted toward what phase plates are used to image as much as the plates themselves.
Shares are the percentage of the 155 records in scope. A patent can carry several IPC classes, so the shares add up to more than 100%.
Go deeper on Phase Plates and Contrast Enhancement with Eureka
This page is one run against one query. Ask Eureka your own question about phase plates and contrast enhancement and every answer comes back with the patent numbers behind it.
Try EurekaA recent filing that defines the current claim boundary
Off-plane imaging mode for a laser phase plate
Phase contrast images in a charged-particle beam system are obtained by directing a CPB as modulated by a sample to a phase plate to have a diffraction plane that is displaced from the phase plate. Based on interference fringes in the images, a transverse displacement of the CPB with respect to the phase plate can be estimated and adjusted.Filed by FEI Company, this record targets the alignment-drift problem directly: it claims a way to measure and correct beam-to-plate displacement from the interference pattern itself, rather than relying on separate alignment hardware.
| # | Publication no. | Patent title | Citations |
|---|---|---|---|
| 1 | US6201592B1 | Liquid crystal display device and method for producing the same | 84 |
| 2 | US7705943B2 | LCD device having vertically aligned liquid crystal layer between first and second substrates in which the fi… | 80 |
| 3 | US20120263648A1 | RNA nanoparticles and nanotubes | 72 |
| 4 | US20050140916A1 | Liquid crystal display device and fabrication method therefor | 48 |
| 5 | US20110267574A1 | Liquid crystal display device and composition for forming liquid crystal layer | 38 |
| 6 | US20180286631A1 | Optical-cavity based ponderomotive phase plate for transmission electron microscopy | 35 |
| 7 | US20130063686A1 | Liquid crystal display device | 34 |
| 8 | WO2019086548A1 | Novel antigen-binding chimeric proteins and methods and uses thereof | 29 |
| 9 | WO2010148085A1 | RNA nanoparticles and methods of use | 29 |
| 10 | US7385660B2 | Liquid crystal display device for transflector having opening in a first electrode for forming a liquid cryst… | 25 |
Citation counts reflect influence within this searched corpus and skew toward older records; they are not a measure of current commercial importance.
Each row carries its publication number; clicking a row searches Eureka by that number.
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Four findings drawn directly from the ranking, trend and classification data — read together, they describe a field with a settled core and a narrowing filing tail.
A short leadership tier, not a crowded field
The top 5 assignees account for 101 of 155 records, and the top 10 push that to 93.5%. With only 51 assignees ranked in total, the remaining entrants each hold a handful of filings — there is a long tail, but it is thin rather than deep.
Cooling from a 2023 peak
Filing rose to 24 records in 2023 before easing to 13 in 2024. Several leading assignees show 0 filings or -100% year-on-year in the latest tracked year, though publication lag means this should be read as a pause in the visible record, not confirmed abandonment.
Biological claims outnumber instrument claims
C07K (peptides & proteins) appears in 47.1% of the 155 records, more than double H01J (electron & discharge tubes) at 20.6%. Most activity in this search sits on the biological-application side of phase plate use, not on the electron-optics hardware itself.
Collaboration is concentrated among a few institutional pairs
Ten co-assignee pairs appear in the data, with the strongest pairing far ahead of the others. This points to a small number of durable academic-institute partnerships rather than broad cross-industry co-filing.
Eureka can read the same corpus for gaps instead of for coverage: under-claimed branches adjacent to phase plates and contrast enhancement, with the prior art for and against each one.
Who holds the ranked positions
The assignee ranking covers 51 companies and institutions counted in records, from a leader with 30 records down to single-digit tenth-place holdings. It is the complete ranking the dataset returns, not a top-50 or top-100 cut.
One assignee sets the pace
The leader holds 30 of the 155 records in scope, well ahead of fifth place at 17 and tenth place at 7. That gap between first and fifth is a large share of the total top-5 concentration.
A defined second tier
Positions two through five hold enough volume between them to make up most of the 65.2% top-5 share, but no single one of them approaches the leader's count — this is a one-plus-several pattern, not a duopoly.
Even active filers are pulling back
The assignee with the most recent-year filing activity still shows a -67% year-on-year drop, and several other leading names show 0 filings in the latest tracked year. Read this against the 18-month publication lag before concluding activity has stopped.
| Assignee | Recent year | YoY |
|---|---|---|
| FEI Company | 1 | -67% |
| The Regents of the University of California | 0 | -100% |
| Vrije Universiteit Brussel | 0 | -100% |
| Vlaams Interuniversitair Instituut voor Biotechnologie (VIB) | 0 | — |
| Sharp Corporation | 0 | — |
| Massachusetts Institute of Technology | 0 | -100% |
| The Board of Trustees of the Leland Stanford Junior University | 0 | — |
| The University of Tokyo | 0 | -100% |
Where to take this analysis
The figures above describe the shape of the field. Turning that into a filing or freedom-to-operate decision means going claim-by-claim against the ranked leaders' active families.
Map claims against the top 5
With 65.2% of records held by five assignees, a freedom-to-operate check should start there before widening to the long tail.
Explore assignee claims in EurekaTrack the 2025-2026 filing tail
Recent-year figures are still filling in under publication lag; revisit momentum by assignee once later data lands rather than treating the current dip as final.
Set up monitoring in EurekaTest white space claims
Under-claimed branches like charging-drift compensation and hole-free plate fabrication warrant a closer novelty check before drafting.
Run a novelty search in EurekaCommon questions about phase plate patents
It is concentrated at the top but not monopolised: the top 5 of 51 ranked assignees hold 101 of 155 records in scope, or 65.2%. The top 10 push that to 93.5%, meaning the remaining 41 ranked assignees split roughly 6.5% of the field between them. This pattern is typical of a technical niche anchored by a handful of research institutions and one or two instrument makers, with a long tail of single- or few-filing entrants rather than a broad competitive middle.
Filing peaked at 24 records in 2023 and eased to 13 in 2024, a documented -38% change from the 2021 level of 21 records. However, publication typically lags filing by around 18 months, so 2025 and 2026 figures in any dataset will look artificially low simply because not all filings from those years have published yet. The honest read is a cooling from a 2023 peak, not a confirmed collapse in activity.
This landscape is scoped specifically to phase contrast and contrast transfer function methods combined with practical failure-mode language such as charging drift, alignment stability and hole-free plate design. That is narrower than electron microscopy broadly, which also covers detectors, sample preparation, and unrelated imaging modes. The IPC mix here — nearly half the records touching C07K peptide claims — shows this specific niche leans heavily toward biological sample applications rather than general instrumentation.
C07K (peptides & proteins) is the largest class, appearing in 47.1% of the 155 records, followed by C12N (microorganisms & genetic engineering) at 29.0% and A61K (medicinal preparations) at 22.6%. The instrument-side classes — H01J for electron and discharge tubes at 20.6% and G02F for optical control and modulation at 12.9% — are smaller but still substantial. Because records can carry multiple IPC codes, these percentages overlap rather than summing to 100%, and a single filing on a hole-free phase plate for small-protein imaging can plausibly sit in several of these classes at once.
The clearest gaps sit in the mechanics of long-term device stability: charging-drift compensation, laser phase plate alignment feedback, and hole-free plate fabrication methods all appear as distinct technical themes in the search terms but are not among the heavily-claimed core. A first filing in one of these areas should focus on a specific correction mechanism — for example measuring beam displacement from interference fringes, as the most recent representative filing in this set does — rather than a broad claim to phase contrast enhancement generally, which sits on dense prior art from the top assignees.
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Disclaimer. This page is generated from Patsnap Eureka data drawn from a limited snapshot of global patent and scientific-literature records, and is provided for general information and reference only.
Patent data carries inherent limitations: recent filings (typically the most recent 18–24 months) are under-counted due to standard publication lag; counts may be reported at either a patent-family or a patent-record basis and are not always directly comparable; classification, applicant-name, and citation data may contain errors, duplicates, or omissions; and the underlying search query defines and constrains the scope shown. As a result, the analysis may be incomplete or inaccurate and may not reflect the full technology landscape.
Nothing on this page constitutes an exhaustive prior-art, novelty, freedom-to-operate, or validity search, nor does it constitute legal, financial, investment, or professional advice, and it should not be relied upon as such. Any patent, commercial, or strategic decision should be verified independently and reviewed with qualified patent, legal, and domain professionals. Patsnap makes no warranties, express or implied, as to the accuracy, completeness, or fitness for any particular purpose of the information presented.
Machine translation. Assignee and organisation names originally recorded in Chinese, Japanese or Korean have been rendered into English by an AI translation step so that the tables stay readable. These renderings are best-effort and may not match a company’s registered English name; the original name is what the underlying patent record carries, and it is what any Eureka query launched from this page uses.