C340 tmd a

The platform structure for assembling the smartphone and other optical/mechanical components was designed using AUTODESK® 123D® DESIGN and prototyped using a 3D printer (Form 2; FormLabs, Somerville, MA, USA). The following components were assembled on the platform: a power LED (365 nm at 3 W; Epileds, Taiwan), a battery-operated micro linear actuator (LA003; Seiko, Tokyo, Japan), a micrometer head (SHS2-13, Sigma), an aspherical lens (C340TMD-A; Thorlabs, Newton, NJ, USA), a long pass filter for emissions (λ = 410 nm, SC-41; Fujifilm, Tokyo, Japan), and a microcomputer system (Genuino 101; Arduino LLC, USA). The aspherical lens was set into the hole beneath which the smartphone camera was inserted. The long pass filter was placed between the aspherical lens and the FRAD (Fig. 1). The micro linear actuator enabled the lateral movement of the sample slide and enabled observation at a 1 cm distance. The micrometer head was used to move the sample slide in the z direction for focusing. The power LED and battery-operated linear actuator were operated via a Genuino 101 board, which communicated to the smartphone through a Bluetooth Low Energy (BLE) module. The size of the smartphone-based platform was approximately 23 × 10 × 7 cm (Fig. S1 †), and the cost was estimated to be <$360 (USD), excluding the smartphone.