## 1 Introduction  
A recent survey about the retinal prosthesis has shown a great interest towards wireless power devices, such as RF antenna and RF harvester IC to restore the image vision for blind people. However, once these wireless power devices are placed on transparent contact lens they could enable the implanted neuron ICs through wireless approach without any cost of external power or battery. The image vision depends upon interior functions of the retina, which respond through light from photoreceptors to the ganglion cells. There are several retina diseases, such as retinal degenerative (RD), retinitis pigmentosa (RP), and age-related macular degeneration (AMD), which are leading causes of blindness, affecting millions worldwide [1]. In order to guard clear vision of blind people, recent technologies required to integrate biological sensors and telemetry. Moreover, an active lens could be used to provide a new tool/methods for research studies without the need for lab chemistry or needles [2]. Figure 1 shows the conceptual layout of wireless interfacing between RF power devices and CMOS neuron IC. The fact is that a contact lens placed exterior to eye could capture image information from the RF wireless video camera, which can pass through the antenna and the RF power harvester IC. The harvested power penetrates into contact lens in the form of light, which passes through photoreceptors to the ganglion cells inside the human eye where retina neuron IC provides appropriate magnitude of read-out spikes for biological image acquisition. The dashed marked figure shows signal flow process from photoreceptors to the brain [3]. A wireless power from external sources has been utilized for stimulation implant in [4; 5; 6]. However, some more reported works have shown interest for various applications, such as retinal prosthesis, neural stimulation, and neural recording. For that purpose, they used inductive coupling coil technique for delivering power and telemetry where data rate and size were not suitable for implantation. From [7; 8; 9; 10; 11; 12; 13; 14; 15; 16; 17; 18], a fully integrated retinal stimulator has been implemented. It enables the new techniques for retinal prosthetic device by adopting the mixed-voltage design, empowering the flexible stimulation patterns, and enhancing the stimulation channels. Moreover, recent technologies offer smart and transparent contact vision lens that fast replaces the bulky inductive coils and the non-scalable implant sizes. In order to build a better display, newly developed contact lens could be used as a platform where devices can be remotely powered, communicate with cell phone, and continuously provide the user with appropriate information. In [19; 20; 21], active lens has initially focused on medical monitoring application by developing an embedded sensor on a contact lens. Moreover, to the best of the authors' knowledge, a fully autonomous integrated system on the retina vision using interfacing approach has not been developed yet. For example, [PERSON] al. [19] have demonstrated an embedded Micro-Electro-Mechanical Systems (MEMS) strain gauge sensor on a contact lens for measuring intraocular pressure. However, the device does not incorporate a telemetry chip and the sensor readout interface involves wired connection to the lens. In [20], the single chip intraocular pressure sensor implanted in the eye's lens had been powered using a 13.56 MHz inductive link with the external unit embedded in spectacle frame. Inductive links offer a relatively short range of operation and the external reader unit needs to be mounted close to the eye. In [21], authors have developed a capacitive pressure sensor on lens but could not implement a read-out circuitry. Figure 1: A conceptual layout at the interface between wireless power devices and complementary metal oxide semiconductor (CMOS) retina neuron integrated circuit (IC) for image acquisition.