Why does the tightly closed cells of the integumentary tissue of the leaf skin not prevent

Why does the tightly closed cells of the integumentary tissue of the leaf skin not prevent the penetration of sunlight into the leaf?

The leaf is an organ of photosynthesis, therefore everything in its structure is subordinated to this function. One of the conditions for this process is the presence of light. The cells of the integumentary tissue, or skin, primarily perform a protective function, which is why they fit so tightly to each other. But, they should not interfere with the passage of light, so the skin cells lie in one layer, they do not have chlorophyll or other pigments, which makes them transparent. And, therefore, the skin does not interfere with the penetration of light rays into the leaf.