Abstract: A wavelength conversion element includes a substrate, a wavelength conversion layer and a heat dissipation member. The substrate has a supporting surface. The wavelength conversion layer is disposed on the supporting surface. The heat dissipation member is disposed on the supporting surface and is surrounded by the wavelength conversion layer. The heat dissipation member has a heat dissipation plate and a plurality of heat dissipation tooth portions. The heat dissipation plate is fixed on the supporting surface. The heat dissipation plate has an outer side surface. The outer side surface is perpendicular to the supporting surface. The heat dissipation tooth portions are respectively connected to the outer side surface. A projection device including the wavelength conversion element is also provided. The wavelength conversion element can improve wavelength conversion efficiency and reliability, and the projection device can improve image brightness and service life.

Abstract: A motion recognition device includes a sensing unit and a processing unit. The sensing unit generates a sense signal in response to a body motion occurring at a specific position on a user's body, wherein the sense signal includes a first sense signal portion and a second sense signal portion different from the first sense signal portion, and the body motion belongs to a motion segment of a motion type. The processing unit processes the sense signal to generate a motion parameter signal structure including a fusion signal of the first and the second sense signal portions, and recognizes the specific position to determine an effective reference signal for recognition of the motion type based on the motion parameter signal structure.

Abstract: A motion recognition device includes a sensing unit and a processing unit. The sensing unit generates a sense signal in response to a body motion occurring at a specific position on a user's body, wherein the sense signal includes a first sense signal portion and a second sense signal portion different from the first sense signal portion, and the body motion belongs to a motion segment of a motion type. The processing unit processes the sense signal to generate a motion parameter signal structure including a fusion signal of the first and the second sense signal portions, and recognizes the specific position to determine an effective reference signal for recognition of the motion type based on the motion parameter signal structure.