The Pronto hardware has two infrared receivers, one in the 'tail' for learning, and another in the 'head' (that the software doesn't support).

The one in the tail has a wide bandwidth, but has a range of only a few inches, to avoid picking up background IR noise. The one in the head has much longer range, but only accepts a narrow range of carrier frequencies (which is somewhat irrelevent, since the software doesn't support it anyhow).

As to the 'description' attributed to Philips, it obviously didn't come from anyone in engineering :-)