Vertically Stacked Perovskite Detectors for Color Sensing and Color Vision

Abstract

Optical color sensors based on perovskites are described. These sensors overcome the limits of conventional image sensors used in smartphones and digital cameras. The sensors allow for detecting the primary colors red, green, and blue without using optical filters. The color sensors consist of vertically stacked diodes using perovskite alloys. The described sensor structure is color aliasing or color moiré error free, while conventional sensors using optical filters are limited by this error. The spectral sensitivity of vertically stacked sensors is up to three times higher than the spectral sensitivity of filter‐based color sensors. The optical constants of the required perovskite alloys are determined, and color sensors are electromagnetically modeled. The spectral sensitivities of the sensors are colorimetrically characterized and compared to sensors in the literature including conventional sensors using optical filters. This study, for the first time, shows that a vertically stacked three color sensor exhibits a color error equal to, or smaller than, errors of conventional sensors using optical filters. Details on the used materials, the device design, and the colorimetric analysis are provided.

Recent Progress in Organic Photodetectors and their Applications

“…[94] By tuning the spectral response, in the meanwhile, they also reported the narrowband red, green, and blue photodiodes without the use of color filters. [95][96][97] Using the CCN concept in organohalide perovskites or mixed lead halides as solution-processable semiconductors, the device exhibited truly filterless narrowband detection with FWHM of less than 100 nm.…”

Highly Sensitive Ultraviolet and Visible Wavelength Sensor Composed of Two Identical Perovskite Nanofilm Photodetectors

“…[1][2][3][4][5] For example, to the conventional sensor employing optical filters. [27] Li and coworkers have synthesized an in situ formed gradient perovskite film with variable absorption edge from 450 to 780 nm, through controlling the heating temperature. By integrating the PDs at different positions of one gradient film, both color detector and spectrometer were demonstrated, which showed a maximum external quantum efficiency over 90% and a spectral resolution of about 80 nm in visible range.…”

“…On the other hand, some new emerging filter-free strategies based on perovskite materials have been investigated in an effort to realize wavelength discrimination, which include the employment of narrowband perovskite, the vertical structure, and the creation of gradient energy band materials. [23][24][25][26][27][28] For example, Meredith and coworkers put forward a charge collection narrowing mechanism in the composite film of organic molecular dyes and organic halide perovskites to control the onset and cutoff wavelength of the spectrum. With this method, tunable narrowband perovskite photo diodes for detection of red, green, and blue illumination, with full width at high-maxima of <100 nm have been fabricated.…”

Light Management in Perovskite Photovoltaic Solar Cells: a perspective

“…Indeed, accurately tuned spectral absorption is required in semitransparent single junction. Moreover, the same concepts can be tweaked to tailor reflectivity spectrum for perovskite-based color printing devices [100][101][102][103] and engineering absorption management in full-color perovskite detectors [104,105].…”