28‐4: Investigation of Moiré Interference in Pinhole Matrix Fingerprint on Display Technology

Abstract

We have investigated the Moiré interference in pinhole based fingerprint on display technology. The origin of the phenomenon is identified as the interference between discrete OLED pixels and the object outline. A countermeasure is given to overcome its impact on the identification of miniature fingerprint features.

Photocurrent diffusion of organic photodetector between pixels for fingerprint sensor by using interdigitated electrodes

“…This analysis is necessary to estimate the optical crosstalk between neighboring pixels for the organic image sensor, especially for the biometric authentication system in the display technology, despite using the spin-coating process due to its simplicity. [6][7][8] In the case of measuring the diffusion photocurrent or crosstalk between pixels, it is very challenging, especially to measure it from a single-pixel sensor. Therefore, we used the IDE structure to measure the photocurrent diffusion from the exposed area to the covered electrodes based on the accumulated current from each covered electrode.…”

“…Under those circumstances, several panel makers are trying to develop an alternative solution based on the pinhole imaging technique. 6,7) Pinhole imaging has been widely known for its immense image quality and straightforward architecture, as shown in Figs. 1(a) and 1(b).…”

“…6) Further study has also been done on the Moiré pattern effect through this imaging system within this application. 7) Although many researchers have established fingerprint recognition using OPDs, there is still a lack of information related to the optical crosstalk between pixels for the organic image sensor. This issue is vital as the crosstalk in the system might give false information on the fingerprint authentication.…”

36‐5: A Novel FOD Solution with High‐PPI Flexible Sensor under OLED Panel

“…A pinhole image system was integrated in the 6inch OLED panel for the benefits of low thickness, high flexibility, and low dependency of OLED panel transmittance [2,3]. The pinhole array was fabricated in an opaque metal layer with the rest area completely shielded.…”

7.4: Investigation of Fingerprint on Display Technology for CFOT Display

“…They show the similar results. When simulating the imaging of this FOD system in folding module by using the same method, a discrete of OLED source should be considered [1]. According to the previous experience, discrete images are often captured on the sensor when measuring FOD with a folding display.…”