A set of point spread functions (PSF) has been obtained by means of Monte-Carlo simulation for a small gamma camera with a pinhole collimator of various hole diameters. The FOV (field of view) of the camera is expended from 45 mm to 70 mm in diameter. The position dependence of the variances of PSF is presented, and the acceptance for the 140 keV gamma rays is explored. A phantom of 70 mm in diameter was experimentally imaged in the camera with effective FOV of only 45 mm in diameter. A set of point spread functions (PSF) has been obtained by means of Monte-Carlo simulation for a small gamma camera with a pinhole collimator of various hole diameters. The FOV (field of view) of the camera is expended from 45 mm to 70 mm in diameter. The position dependence of the variances of PSF is presented, and the acceptance for the 140 keV gamma rays is explored. A phantom of 70 mm in diameter was experimentally imaged in the camera with effective FOV of only 45 mm in diameter.