Tactile sensor and fingerprint sensor using same

#The present invention relates to a fingerprint sensor, and more particularly to a fingerprint sensor, which is compact and can be mounted in a very thin sheet.

#An optical fingerprint sensor is known, which uses a prism and a photoelectric converter. The photoelectric converter converts incident light rays reflected by ridges and valleys of finger surface that is in contact with a surface of the prism.

#A fingerprint sensor using a pressure sensitive sheet is known. Arranged in a matrix form on the pressure sensitive sheet are electrodes, Distribution of electrical resistance over the whole area of the sheet is altered by ridges and valleys of finger surface that is in contact with a surface of the sheet.

#FIG. 1 is a schematic a plan view of a first embodiment of a tactile sensor.

#FIG. 2 is a section taken through the line 2--2 in FIG. 1.

#FIG. 3 is a similar view to FIG. 2 illustrating a second embodiment of a tactile sensor.

#Referring to the accompanying drawings, the embodiments according to the present invention are described.

#[First Embodiment]

#FIGS. 1 and 2 show a source region 1, a source electrode 2, a member of electrically conductive material or gate electrode 3, a drain region 4, an elongate elastic insulating body 6 of insulating material, an insulating film 7, and a silicon (Si) substrate 8.