抄録
In this paper, we propose a new method that can estimate contact force and finger angle for touch panel devices by measuring transmitted light on fingernail. When we touch a light source with our finger, the light (mainly red component) can be seen at the fingernail since the red light can go through the finger tissue. Based on this characteristic, we can estimate the manipulatory force by detecting the light intensity at the fingernail because the intensity of the transmitted light is proportional to the applied force. We can also estimate the relative direction of the finger to the touch panel device. Even though the transmission through the finger tissue is diffusive one, we can know the movement of the light source below the finger with camera attached onto the fingernail. Therefore, a transient pattern of the light source is useful for estimating the relative direction between the finger and the device.
