The Pixel Detector of the ATLAS experiment at LHC is described with emphasi
s on recent developments. The ATLAS pixel detector consists of three cylind
rical layers in the barrel part and of two times five disk layers in the fo
rward and backward parts. The system is designed to operate with 40 MHz bun
ch crossing frequency, high particle flux densities and extreme radiation e
nvironment at LHC. The project is presently entering the pre-production and
production phase for a number of items. Design features of the detector an
d prototype results are presented. (C) 2001 Elsevier Science B.V. All right
s reserved.