What do those red marking do (just to the right to the focus distances?
It looks like a Chinon 40-150mm f/3.5 zoom, correct?
In either case, those are focus marks for infrared photography.
Infrared light will focus at a different point than visible light, so if you want to make infrared pictures you'll use one of the red markers instead of the white mark for the focus scale.
There are multiple red marks because the IR focus varies with the zoom setting, so you'll use the red
105 mark when the zoom is at 105 mm, etc.
Many older lenses have some sort of focus marking for IR, here are a few common variants.
If you have a digital camera, it will most likely have a built-in UV/IR-block filter, so the sensitivity to IR wavelengths is very low. With the help of an IR-pass filter (which blocks visible light), a tripod, and long exposures, IR photography is still possible.
The IR sensitivity of digital cameras can be improved by removing the built-in filter. To get an approximate idea of how much difference it makes, see this page on DSLR modding, which compares a modded and an unmodded DSLR on a 940nm IR remote. Briefly, the test indicated about 10 stops increase in sensitivity after modding. For that wavelength, those cameras, and those test conditions.
Those markings are for focusing infrared. Infrared light focuses at a different point to visible light. It will also vary with zoom length. To focus at infrared on that lens you would select the mark witch matches the zoom you are using. Then you would match this mark with the correct distance from the focus ring above.