A virtual touch screen concept using an optical see-through head-mounted display has been suggested. With a virtual touch screen, the user's direct-touch interactions are allowed in much the same way as a conventional touch screen, but the absence of haptic feedback and physical constraint leads to poor user performance. To overcome this issue, we developed a wearable haptic device, called HapThimble. It provides various types of haptic feedback (tactile, pseudo-force, and vibrotactile) to the user's fingertip and mimics physical buttons based on force-penetration depth curves. We conducted three experiments with HapThimble. The first experiment confirmed that HapThimble could increase a users' performance when conducting clicking and dragging tasks. The second experiment revealed that users could differentiate between six types of haptic feedback, rendered based on different force-penetration depth curves obtained using HapThimble. Last, we conducted a test to investigate the similarity between the physical buttons and the mimicked haptic buttons and obtained a 90.3% success rate.