Diffractive imaging lens based on multiplexing of wavelength in full visible band

Diffractive optical element (DOE) has attracted much attention due to their remarkable ability to precisely manipulate the phase and amplitude of light waves through carefully designed surface microstructures. However, the inherent wavelengthdependent characteristics of DOEs significantly constrain their applications in multi-wavelength and broadband scenarios. This study presents the design and experimental demonstration of two distinct types of wavelength-multiplexed planar diffractive lenses capable of full-visible-spectrum multispectral imaging and achromatic imaging, respectively. Firstly, we designed and numerically validated a multispectral imaging diffractive optical lens (MSI-DOL) based on wavelength multiplexing, achieving 12-channel spectral imaging within the full visible spectrum (425–700 nm). Furthermore, by integrating wavelength multiplexing with a particle swarm optimization (PSO) algorithm, we proposed and experimentally demonstrated a full visible achromatic diffractive lens (FV-ADL). The FV-ADL, fabricated via three-dimensional laser direct writing, features a diameter of 2 mm and a focal length of 20 mm. Imaging experiments confirmed that the fabricated ADL achieves near-diffraction-limited achromatic performance over the 450–700 nm wavelength range, consistent with theoretical predictions. The proposed design and experimental validation of multispectral and achromatic diffractive lenses advance the imaging functionalities of DOEs with less fabrication complexity and capable of large aperture, offering a novel approach to compact and integrated optical systems for multispectral and broadband achromatic imaging.