I am currently using a Keyence LB-1101 laser distance finder with the LB-081 head. I would like to use the analog pins as input from the output of the device. The issue is that in a certain range the device outputs a negative signal, so anything between 80mm - 95MM is 0v-+5V while 65mm-80mm is -5v-0v. How can I read the negative input from the device without damaging my Arduino? If anything is unclear just tell me in the comments and I will try to clarify.
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You will need external circuitry to bias and condition the output to the 0-5V range. Arduinos cannot accept negative input voltages.
An operational amplifier and a few resistors will do the job, but that will also require a bipolar power supply.
Alternatively, you could buy a bipolar ADC module and use that to convert the sensor output to digital.
A 1:1 voltage divider with it's fixed point not connected to ground but to 5volt might be enough.
(depending on the output impedance of the sensor)
Try a 10k resistor between sensor output and Arduino analogue pin,
and a 10k resistor between analogue pin and 5volt.
Leo..