FR537556A - Developments in portable microphonic devices for the deaf - Google Patents

Developments in portable microphonic devices for the deaf

Info

Publication number
FR537556A
FR537556A FR537556DA FR537556A FR 537556 A FR537556 A FR 537556A FR 537556D A FR537556D A FR 537556DA FR 537556 A FR537556 A FR 537556A
Authority
FR
France
Prior art keywords
deaf
developments
portable
microphonic
microphonic devices
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired
Application number
Other languages
French (fr)
Inventor
Paul-Joseph Franck-Valery
Raoul-Vidal Franck-Valery
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed filed Critical
Application granted granted Critical
Publication of FR537556A publication Critical patent/FR537556A/en
Expired legal-status Critical Current

Links

Classifications

    • G—PHYSICS
    • G02—OPTICS
    • G02C—SPECTACLES; SUNGLASSES OR GOGGLES INSOFAR AS THEY HAVE THE SAME FEATURES AS SPECTACLES; CONTACT LENSES
    • G02C11/00—Non-optical adjuncts; Attachment thereof
    • G02C11/06—Hearing aids

Landscapes

  • Physics & Mathematics (AREA)
  • Health & Medical Sciences (AREA)
  • Acoustics & Sound (AREA)
  • General Health & Medical Sciences (AREA)
  • Otolaryngology (AREA)
  • General Physics & Mathematics (AREA)
  • Ophthalmology & Optometry (AREA)
  • Optics & Photonics (AREA)
FR537556D 1921-03-15 1921-03-15 Developments in portable microphonic devices for the deaf Expired FR537556A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
FR537556T 1921-03-15

Publications (1)

Publication Number Publication Date
FR537556A true FR537556A (en) 1922-05-26

Family

ID=8927587

Family Applications (1)

Application Number Title Priority Date Filing Date
FR537556D Expired FR537556A (en) 1921-03-15 1921-03-15 Developments in portable microphonic devices for the deaf

Country Status (1)

Country Link
FR (1) FR537556A (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2946394A (en) * 1954-01-18 1960-07-26 Alonzo L Smith Air-conduction hearing aid clamps
US5579400A (en) * 1992-07-17 1996-11-26 Ballein; Burkhard Headphones

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2946394A (en) * 1954-01-18 1960-07-26 Alonzo L Smith Air-conduction hearing aid clamps
US5579400A (en) * 1992-07-17 1996-11-26 Ballein; Burkhard Headphones

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