How to get more analog input's without multiplexing?

for a project I'm currently working on, I've stumbled on some problems..
the idea is just a table drilled 1000 .75mm holes in it. each hole will have a fibre optics.
it started with just a tablet wich works, but is small. I wanne upscale to a table.

10sensor's, 20led's, 10x940nm IR will become now:

30sensors (2leg black IR recv), 50led's (blue), 30x940IR.
the 50 led's are no problem those I can just do with some 74HC595's.
the 940nm IR emitter's have it's own circuit without controller, it just needs to constantly burst IR signals.

but how can I read out the value of 30 sensor's???

how it all works (tablet version)

the IR emits signal constantly in burst (using delay timers)
the IR recv constantly reads out the light value from the IR, doesn't need to be simultaneously, but can alternate an array with low delaytime.
when moving hand above the table recv value changes & matching led's light up (to the led's are package of 20fibre's with shrink seal to transfer light to table.
wich gives a moving water pattern on the tableTop.

how can I read out all the sensor's but without multiplexing?
can I just put some extra ATMega bootloaders (hackduino) with crystal & connect it to an Arduino UNO or esp32?
everything comes on a custom pcb, since the led's are also on the pcb, I can just scale it up to solder extra components, but I don't want a second Arduino or esp32

any suggestions, or other maybe better solutions for my project?
I've tried with just lrd's but when it's pitch black in the room ldr doesn't work anymore...
pir sensor's are to big of a size..

phototransistors??? haven't got experience with..

Have you ever used a diode for something? A phototransistor is a diode that conducts when illuminated.

No i haven’t.. that’s why i ask.. haven’t got experience with it..
but since you says it like that, phototransistor is unusable for my project..
at night there’s no illumination..

Only got experience with led’s
Light emiting diode..
& zener diode i know as a one way solution so current can’t flow back

Now I am really confused. You original post describes a system with fiber optics driven by LEDs. Then sensors are mentioned, so I assumed they were light sensors of some type. Please give an example of the sensors you are using and how this all is supposed to work.

I think pictures and part numbers are needed to provide meaningful help.

Why do you think multiplexing can/should not be used?

How will you circumvent the multiplexer inside the Arduino?

With Arduino you can pin-multiply by wiring more chips.

IR 940nm led is used for making invisible light to work in the dark.
Ir receiver (2leg black led) is used to measure the light, if hand goes above value changes & blue led’s are turned on (the head of the led i’ve put in heatshrink with 2optic fibre’s..

So ir940 emiter is constantly lighting,
Ir receiver (flamesensor) is measuring lightintensitie..
because of the invisible light emiting (ir) it’s possible to use it in the dark.

If flamesensor detects a change in value ledpin is turned high.
If it’s starting value it remains low.

But because of the size of the table i need 30 ir receivers to measure.

I’ve read multiple times that analog readings with multiplexing isn’t very accurate..??

I've read often that the earth is flat.

And I'm still missing your concept to circumvent the built-in mux.

Learning goes along with reading.. can’t know everything in the world.. i’ve got no concept with multiplexing.. only concept i have is the working tablet with an esp32.. got enough inputs & outputs.. so just connected everything, write code for it & was working..
Now i just want to expand the same to a table but i’ll need 30inputs to cover the table.

I don’t know anything about multiplexing or so.. but i’ve read that it wasn’t that accurate.. is it true or not i don’t really know..

Just a starter in electronics & programming..

It's not a good idea to start mega projects, if you have basically no clue about the basics.

Have a look at the datasheet of a common chip

https://www.onsemi.com/products/interfaces/analog-switches/mc14067b

If your ESP32 has two analog inputs,
two of those chips would allow you to access 32 analog sources.

From a wiring perspective, using serial RGB LEDs like the ws2812b could make sense.
Those need one or two connections beside 5v and GND and are daisy-chained.

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