Provided is an illuminating device in which incident light from a light source can achieve a uniform irradiation effect according to an irregular shape of a plant and contribute to improvement of plant growth. A light source 101 that emits incident light L, and a light-form generating member 102 that is provided on one side of the light source 101 and receives the incident light L. The incident light L is transmitted through the light-form generating member 102. The transmitted light L1 is generated, and the transmitted light L1 generates the light shape 104. The light shape 104 forms a light intensity distribution in which the light intensity close to the light source 101 and the light intensity away from the light source 101 are equal. [Selection] Figure 1【課題】光源からの入射光が、植物の不規則な形に応じて、均一な照射効果を達成し、植物の生長を改善することに寄与することができる照明装置を提供する。【解決手段】入射光Ｌを発出する光源１０１と、光源１０１の一側に設けられ入射光Ｌを受ける光形発生部材１０２と、を含み、入射光Ｌが光形発生部材１０２を透過して透過光Ｌ１を発生させ、透過光Ｌ１が光形１０４を発生させ、光形１０４によって光源１０１に近い光強度及び光源１０１から離れる光強度が等しい光強度分布を形成する。【選択図】図１
