There is a trivial answer: decide of a daily password, print it on a pass and you have exactly the system you're describing: a "pattern" that is printed on a physical medium, that can be check by a human being without any extra device or hardware.
If you're willing to rfelax requirement a bit, there is a technique called "visual cryptography" that does something a bit similar but that also requires the person performing the validation to have access to a specific piece of hardware (in this case, a transparent mask which - which can be printed whenever needed).
The Wikipedia article linked has a good, simple example of such an algorythm:
There is a simple algorithm for binary (black and white) visual
cryptography that creates 2 encrypted images from an original
unencrypted image. The algorithm is as follows: First create an image
of random pixels the same size and shape as the original image. Next,
create a second image the same size and shape as the first, but where
a pixel of the original image is the same as the corresponding pixel
in the first encrypted image, set the same pixel of the second
encrypted image to the opposite color. Where a pixel of the original
image is different than the corresponding pixel in the first encrypted
image, set the same pixel of the second encrypted image to the same
color as the corresponding pixel of the first encrypted image. The two
apparently random images can now be combined using an exclusive-or
(XOR) to re-create the original image.
This simple technique has several disadvantages, however: first, anyone having access to a valid access pass can reproduce it very easily, even without understanding the code. second, you need to roll out the validation mask to everyone each time you generate a new access password. Third, all access are equivalent.
There are more advances algorythm that are more flexible (for instance, that will use a single mask to generate a different output depending on th input which, in turn could be used for discriminating between different access rights or simple making each access pass unique).