Color detection is one of the top interests in both biological and industrial applications. Specifically, the Determination of the light wave characteristics is vital in photonic technology. One of the features in the color sense that should be found out is its wavelength or color. In this work, we propose a structure that can be used to detect RGB colors separately in an efficient way. The proposed detector consists of the plasmonic filter sensing desired wavelength (red, green, and blue) and the PN diode to convert the received photons to the electrical current. At the input intensity of 1 mW × cm⁻², the current density for blue, green, and red colors are 27, 35, and 48 µA × cm⁻², respectively. It is shown that the intensities needed to obtain the current densities of 0.1 µA × cm⁻² are 3.94, 2.98, and 2.25 µW × cm⁻² for the blue, green, and red spectra respectively. It should mention that by using high-precision photodetector structures such as PIN diode, the minimum detectable level can be decreased. Simple adjusting for desired wavelength and linear operation for different input intensities are the characteristics of the designed structure. This detector is compatible with CMOS technology and can be easily utilized in numerous applications, such as charge-coupled devices, displays, and cameras.

Color sensors have broad applications in spectroscopy, medical imaging, and CMOS-based cameras. One of the fundamental challenges in this field is implementing a dynamically tunable filter capable of covering the visible spectrum; hence, designing a tunable filter with high spectral resolution and a narrow bandwidth frequency response is essential. In this work, a multilayer color sensor based on Fabry-Pérot resonance is designed, offering the capability for static and dynamic tuning of the transmitted wavelength and the ability to detect different colors in an integrated device, including a filter and detector. The filter comprises four parts: blue, green, yellow-orange, and red. The detector is a simple PN photodiode. The dynamic adjustment is performed via the voltage applied to the filter. In addition to the dynamic tunability, a key characteristic of this structure is its bandwidth, which remains consistently below 9, 8.5, 8, and 11.5 nm for blue, green, yellow-orange, and red regions, respectively. Notably, the materials used in this structure have been selected to be compatible with CMOS technology. Another feature of this sensor is its 50 nm spectral shift for each specified spectrum, achieved with a 15-volt bias. Furthermore, this device presents minuscule crosstalk (below 5%) compared to other devices.