A PCB business card with a batteryless LED, powered by the phone that taps it
A new business card design uses a printed circuit board and a tiny LED that stays off until a phone’s NFC or Bluetooth signal powers it. The card contains no battery; instead, the phone’s radio energy is harvested to light the LED, allowing the card to display a message or logo on demand. The concept demonstrates ultra‑low‑power, contactless illumination for marketing.