Without backlight, the display content of the last screen can be maintained for a long time after power failure The power consumption is very low, basically only when the play is new E-ink screen can clearly display the picture under ambient light such as light and , without backlight, and the visual angle is almost 180 degrees . Because it is comparable to the display effect of traditional paper, it is often used in applications such as . The application scenario is applicable to mall price labels, asset equipment labels, electronic shelf labels, conference , etc The electronic ink screen uses the "microcapsule electrophoretic display" technology for image display. Its working principle is that the nanoparticles suspended in the liquid migrate under the action of electric field, and the display effect close to the traditional printing paper is formed by reflection under ambient light. Working voltage: 3.3V Communication interface: 3 wire SPI, 4-wire SPI Gray level: 2 Dimensions: 37.32x31.8x1.05mm Global refresh: 8s Display size: 27.6x27.6mm Refresh power consumption: 264 mw (typ.) Dot pitch 0.138x0.138mm Resolution: 200*200pixels Colour:White Material:ABS Package Contents: 1 x 1.54 Inch Ink Screen Only the above package content, other products are not included. Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.