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PCE
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CPC Subgroup
H04R 1/38

in which sound waves act upon both sides of a diaphragm and incorporating acoustic phase-shifting means, e.g. pressure-gradient microphone

Full Title

Details of transducers, > Arrangements for obtaining desired frequency or directional characteristics (for stereophonic purpose H04R5/00) > for obtaining desired directional characteristic only > by using a single transducer with sound reflecting, diffracting, directing or guiding means > in which sound waves act upon both sides of a diaphragm and incorporating acoustic phase-shifting means, e.g. pressure-gradient microphone

Top Applicants

Top 10 applicants by patent filingsfor class H04, 2013–2023, worldwide · Source: EPO PATSTAT

  1. HUAWEI TECHNOLOGIES COMPANY CN 101,476
  2. QUALCOMM US 101,139
  3. SAMSUNG ELECTRONICS COMPANY KR 96,655
  4. TELEFONAKTIEBOLAGET LM ERICSSON (PUBL) SE 57,744
  5. LG ELECTRONICS KR 55,253
  6. HUAWEI TECHNOLOGIES COMPANY 54,181
  7. SONY CORPORATION JP 35,309
  8. ZTE CORPORATION CN 32,950
  9. INTEL CORPORATION US 27,533
  10. GUANGDONG OPPO MOBILE TELECOMMUNICATIONS CORPORATION CN 27,498