O2 Sensor Question

[Brian Franchuk]

I just looked at the LAF O2 sensor web page at 
http://www.tech2tech.net/training/laf.htm and I thought of some 
questions:

1) What is the detection range of a typical lambda sensor?  I've 
   heard the range is very narrow.  

2) Can the detection range be increased?  The web page talks about 
   using a voltage to repel the oxygen ions to control the rate that
   the ions reach the diffusion chamber.  If voltage is applied to a 
   normal sensor, what will happen?  

Is there is good web page or book I can look at for more info.

Thanks

Brian F.