The upconversion properties of β-NaYF4:Yb3+(10%),Er3+(1%) microprisms under different excitation conditions

► The UC properties of β-NaYF4: Yb3+ (10%),Er3+ (1%) microprisms under different excitation conditions were studied. ► The UC emission of β-NaYF4:Yb3+ (10%),Er3+ (1%) is very sensitive to the power of the 980 nm laser. ► The UC emission of β-NaYF4:Yb3+ (10%),Er3+ (1%) is almost independent of the power of the 1560 nm laser. ► A current density of 64 μA/cm2 was measured under 0.53 W/cm2 980 nm laser excitation.