Sensor grid

Hello,

I'm working on a project that uses 16 light sensors in a 4x4 grid.

What ways are there to minimise the amount of pins I have to use for the sensors?

That would depend on the type of light sensor.

They are basic photocells with 2 leads.

Hi, Do you need accurate analog values? Or just On-Off?

They are basic photocells with 2 leads.

That narrows it right down to photodiodes, two-lead phototransistors, old fashioned vacuum phototubes and light dependent resistors.

terryking228:
Hi, Do you need accurate analog values? Or just On-Off?

On-Off. I just need to know if there is an object covering the sensor.

jremington:
That narrows it right down to photodiodes, two-lead phototransistors, old fashioned vacuum phototubes and light dependent resistors.

I do not know what kind. My teacher said he would get me some photocells. He hasn't responded yet to my question of what kind or model they are.

The project is on hold until the teacher gets back to you.

Nudge. Looking at this same problem.
I have a circuit from a device with a 4x4 grid of LDRs.
I would like to get a simple on/off from this array.
Any help would be appreciated.
Thanks.

So connect them to two shift registers, or two 8-channel ADC chips, and read all the values in.
Either 0/1 for shift registers, or 0-255 or 0-1024 or 0-4096 for ADCs and make a decision based on the values read in.
12-bit ADC for example:
https://www.digikey.com/product-detail/en/microchip-technology/MCP3208-CI-P/MCP3208-CI-P-ND/305928