Create raster pattern in printable format for use with retro computing optical mouse

[Jacky_BEL]

I have an early serial optical mouse that uses a metal base plate with a raster pattern printed on it for the optical sensor to determine movement.
I have now found a service that can print personalized pictures on mousemats.
So I want to try out if i can replace the metal plate with such a mousemat.
For that, I need to recreate the raster pattern, but I don't have any graphical software.
What would be the easiest and quick way to create such a pattern?

 

[Macro Device]

What would be the easiest and quick way to create such a pattern?

Visiting a print lab, saying, "could you please draw this pattern for me?"
Or, if you're not into feeding printing companies you can download Paint.net (it's free) and see if you can draw it.

 

[Tahagomizer]

The easiest way I can think of would be to just take a photo of the pattern, maybe use a free/online photo editing tool to improve contrast.

 

[Athlonite]

I have an early serial optical mouse that uses a metal base plate with a raster pattern printed on it for the optical sensor to determine movement.
I have now found a service that can print personalized pictures on mousemats.
So I want to try out if i can replace the metal plate with such a mousemat.
For that, I need to recreate the raster pattern, but I don't have any graphical software.
What would be the easiest and quick way to create such a pattern?

Are you ably to put up a pic of the mouse pad so we can see the type of pattern on it that way we could advise you better about how and what you could do to replicate it

 

[Jacky_BEL]

It is just a fine square grid pattern.
The surface of the mouse pad is a bit larger than the metal plate, so just copying and zooming in or enlarging is not an option.
I am trying to count or measure the line density somehow (and will post a pic when able).

The printing service is just a hobbyist and used to mainly print travel pictures or portraits on mousepads and not very much tech oriented i might add.
I can not expect help in that sense. I expect that scaling will occur. I asked about some details of the printer to get the same line density on the mousepad.

<- this is what the pattern looks like upclose

It really is a simple repetitive pattern, like 3 black tiles and 1 reflective tile in a square configuration, and then repeat sideways and downward.
I can measure 3 patterns per mm. If a printer could print perfect square "dots" it would equate to 150 dpi.