An optical distance measurement system includes a transmission circuit and a receive circuit. The transmission circuit is configured to generate narrowband intensity modulated light transmission signals over a first band of frequencies and direct the narrowband light transmission signal toward a target object. The receive circuit is configured to receive reflected light off the target object, convert the reflected light into a current signal proportional to the intensity of the reflected light, filter frequencies outside a second band of frequencies from the current signal to create a filtered current signal, and convert the filtered current signal into a voltage signal. The second band of frequencies corresponds with the first band of frequencies.