Need some help regarding antenna arrays

hello everyone, I am designing a uniformly spaced antenna array of same elements in which I want to use each antenna element smaller than its original dimension by applying the size reduction techniques like introducing slots, shortening pins etc etc.

My question is that what should be the inter element distance as the optimal distance for normal arrays must be less than or equal to half of lambda, but in this case if I take half lambda inter element distance, it will be too large as compared to size of single element.

please share your knowledge if any one knows about it?