A display panel and display device having the same are provided. The display panel includes a quantum dot color filter layer configured to convert a color of light; a transparent front substrate provided at a first side of the quantum dot color filter layer; and a low refractive layer provided between the quantum dot color filter layer and the front substrate, the low refractive layer having a refractive index that is lower than a refractive index of the quantum dot color filter layer.

Optical states in TIR-based image displays may be modulated by movement of electrophoretically mobile particles into and out of the evanescent wave region at the interface of a high refractive index convex protrusions and a low refractive index medium. The movement of particles into the evanescent wave region may frustrate TIR and form dark states at pixels. Movement of particles out of the evanescent wave region may allow for TIR of incident light to form bright states at pixels. The movement of the particles may be controlled by employing the drive methods of pulse width modulation, voltage modulation or a combination thereof.

An optical modulator may include: a first semiconductor layer; a second semiconductor layer configured as a micro-disk, the second semiconductor layer being on the first semiconductor layer, and the second semiconductor layer including a first doping region and a second doping region, wherein a doping concentration of the first doping region is higher than a doping concentration of the second doping region; a first optical waveguide adjacent to the second semiconductor layer; a first electrode layer on the first doping region; and a second electrode layer on the first doping region and spaced apart from the first electrode layer, wherein the second semiconductor layer includes at least one recess, the second semiconductor layer has at least one step difference due to the at least one recess, and each of the first doping region, the second doping region, and the at least one recess includes a circular shape that is concentric with respect to one another.