LENS UNIT AND PROJECTION DEVICE

To provide a lens unit which has enhanced its dust-proof performance while being downsized, and a projection device.SOLUTION: A lens barrel 80 comprises: a first internal cylinder body 120 holding a zoom lens; and an outer cylinder body 130 covering at least a part of the first internal cylinder body 120. The first internal cylinder body 120 includes: a first male groove 121a provided on an outer peripheral surface; and a knob 126 provided projectingly on the first male groove 121a. The outer cylinder body 130 includes: a first female groove 133a provided on an inner peripheral surface and connecting to the first male groove 121a; and a knob aperture 130A1 which is open along the first male groove 121a. The knob 126 projects from the knob aperture 130A1.SELECTED DRAWING: Figure 3 【課題】小型化を図りつつ、防塵性能を高めたレンズユニット及び投影装置を提供する。【解決手段】レンズ鏡筒８０は、ズームレンズが保持される第１内側筒体１２０と、第１内側筒体１２０の少なくとも一部を覆う外側筒体１３０と、を備え、第１内側筒体１２０は、外周面に設けられた第１雄溝部１２１ａと、第１雄溝部１２１ａ上に突設された取手１２６と、を有し、外側筒体１３０は、内周面に設けられて第１雄溝部１２１ａと接続する第１雌溝部１３３ａと、第１雄溝部１２１ａに沿って開口する取手開口部１３０Ａ１と、を有し、取手１２６は、取手開口部１３０Ａ１から突出する。【選択図】図３