Abstract: An encapsulated reflective sensor for use in conjunction with a code wheel for determining the motion and position of a shaft has a light emitting device and photodetector array contained within a transparent encapsulant. The encapsulant has a convex curved surface which prevents light from the light emitting device from impinging on the photodetector array. An emitter lens is formed by the convex curved surface between the light emitting device and the code wheel. The emitter lens magnifies and concentrates the light toward the code wheel. As the code wheel turns with the shaft, the light incident on the wheel is modulated and reflected toward the photodetector array. A second detector lens may be used between the code wheel and photodetector array for concentrating the modulated light reflected from the code wheel toward the photodetector array.