## 2 Related Work  
There are many studies and devices that have attempted to transfer the haptic sensation to the body to enhance the immersive experience. There are reports of wearable and installed type devices that are embedded with vibrators to provide tactile feedback [9; 10; 11]. There are also a few reports on haptics displays developed for use in VR/AR [12; 13; 14]. However, most of them are not based on tactile transfer. Tactile transfer, in which tactile information from one part of the body is transferred to other parts of the body, is a common method in the study of prosthetic hands, and there have been many attempts to place motors and eccentric vibrators on the arms and shoulders [2; 3; 15]. The study aimed to expand human tactile perception by using a method  
Figure 1: **(a)** Fingertip sensing glove, **(b)** haptics vest, **(c)** inside of haptics vest, **(d)** output of fingertip sensing glove and haptics vest (for example, when touching a model of a horizontal line “-” and cross “\(\times\)” the value output by the pressure sensor is visualized, and the part where the actuator of the tactile vest is driven corresponding to the pressure sensor is shown). known as assistive devices. However, these devices could transmit haptic sensation only symbolically using vibration or electrical stimulation and could not recognize the shape of objects or support human skills. Similarly, there are some examples of applying tactile transfer technology such as VR technology. [PERSON] et al. performed a large-area tactile presentation on the soles [16]. In this study, a mapping of palmar tactile sensations to the soles of the feet was demonstrated, which can be considered intuitive because of the similarity of the shapes of the palms and soles. The tactile information of the fingertips has also been transferred to the arm using a five-segment linking mechanism [3], to the face using an air-driven suction device [5], and to the wrist using a bracelet-type device [17; 18; 19]. However, most of these studies treated fingertips as a single contact point, and none used a dense wearable tactile sensor to transfer high density tactile information acquired by a single finger. For extending the tactile ability of the human body, a fingertip-mounted microscope that magnifies a touched area haptically was proposed [20]. It could connect the micro and macroscopic worlds through intuitive fingertip movements. In addition, there are studies that provide feedback on the pressure distribution at the fingertip to the finger skin using electrical stimulation [21]. Although the extension of fingertip sensing capabilities was achieved, the haptics display itself inhibited the movement of the fingers. There were several researches on tactile cue presentation on the abdomen and back [10; 22], but as far as the authors know, they did not intend to transfer fingertip tactile information. Here, we demonstrate tactile transfer based on the following idea. A large number (80) of tactile presentation elements are placed in a large area on the back to present the tactile information of the finger with sufficiently high resolution. The fingertip is fitted with a glove that can sense the pressure distribution at the fingertip with 2-mm resolution, which is equivalent to the two-point discrimination threshold of the fingertips. We aim to extend the human ability by reconstructing the tactile ability of the hands on the back. If we consider the tactile ability as the number of discriminable tactile points, the area divided by the resolution, we can increase the number of tactile points on the back, so that the tactile presentation on the back exceeds the tactile ability of the fingertips. There have been studies in which vibrators are placed on the back and vibration stimuli are applied as an output, such as a study that realized navigation of walking for visually impaired and healthy people [23; 24].