Homozygous means there are two dominant or two recessive genes. In the case of the female, it is dominant, so her genotype is LL. In order for the male to have short eyelashes, he must be homozygous recessive, or ll.
When you cross LL by ll, you will end up with Ll, Ll, Ll, Ll, or 100% heterozygous dominant genotype. The genotype ratio of the offspring is 1:1.
Hope this helps =)