Ear / Oreille
Ear recognition uses mainly two features :
- The shape of the ear: ear geometry
- The canal of the ear which returns a specific echo
Deux caractéristiques de l'oreille sont exploitées pour l'identification :
- La forme du pavillon de l'oreille: géométrie de l'oreille
- Le tuyau de l'oreille a un écho spécifique

A good starting paper on this subject :
Un bon article pour commencer sur ce sujet :
- Ear biometrics Hanna-Kaisa Lammi from Lappeenranta University of Technology,
- As well as FearID, a european project on this subject.
Ear geometry
Ear geometry recognition uses the shape of the ear to perform identification
La reconnaissance par la géométrie de l'oreille utilise la forme du pavillon de l'oreille pour l'identication

An infrared image can be used to eliminate hair:
Une image infrarouge peut être utilisée pour éliminer les cheveux:

Here is a paper about ear shape recognition using a specific method :

- Automatic ear recognition by force field transformation / Hurley & als (University of Southampton)
- (2004) The University of Notre Dame has collected a database, with the university of South Florida are studying this biometrics.
- (2005) ICP-Based Approaches for 3D Ear Recognition / Yan, Bowyer, Chang (Univ. of Notre-Dame)
- (2019) Ear biometrics recognition using laser biospeckled fringe projection profilometry / Amit Chatterjee, Puneet Singh, Vimal Bhatia, Shashi Prakash.
Earprint in forensics: sorry, all my old links are dead.
Ear canal feedback / Echo du tuyau de l'oreille
The acoustic response of the ear canal depends on its geometry.
Beginning of 2003, Dr. Andrew Brown from the university of Southampton has proposed to identify persons using the ear canal echo.
La réponse acoustique du canal de l'oreille dépend de sa géométrie.
Début 2003, le Dr. Andrew Brown de l'université de Southampton a proposé d'identifier les gens grâce à l'écho du canal de l'oreille.
- (2004) Using Otoacoustic Emissions as a Biometric
Matthew A. Swabey, Stephen P. Beeby, Andrew D. Brown, John E. Chad - Otoacoustic emissions provide individual identities (dead link)
- University of Southampton, ISIS but the link to ear is broken
- (2004) Philips (Mr Tuyls) is also working on that subject. No website.
- (2012) Transient Otoacoustic Emissions for biometric recognition
Jiexin Gao ; Agrafioti, F. ; Siyuan Wang ; Hatzinakos, D. (Edward S. Rogers Sr. Dept. of Electr. & Comput. Eng., Univ. of Toronto) - (2016 Mar) NEC develops biometrics technology that uses sound to distinguish individually unique ear cavity shape. New, they said...

Commercial products
The Optophone (Optophone Ear Shape Verifier) was a camera looking like a telephone to capture an image of the ear. It was manufactured by ArtTechniques, a french company. No more information available.
L'Optophone était une caméra qui ressemblait à un téléphone pour prendre une photo de l'oreille, fabriqué par ArtTechniques, une compagnie française. Aucune autre information n'est disponible.
- This patent from Patrick-Ralph Macron:
dispositif de reconnaissance anthropométrique d'un individu
Descartes Biometrics
- (2014) The Descartes Biometrics
introduces ERGO, a ear recognition application to unlock your phone.
Likely using the capacitive sensor of the screen.
Helix is using the camera, so the image.
Yahoo
- (2015 Apr) In a project presented at the 2015 Computer-Human Interaction Conference (CHI) in Seoul, Yahoo showed that other body parts can unlock phones in a fast, secure manner.
