An indicator (8, 35) which emits a light, the indicator (8, 35) comprising: a plate-shaped member (22, 33) which has a stress-concentrating section (16, 27, 41, 49, 53, 57) which causes a stress concentration, and a stress-transmitting section which is connected to the stress-concentrating section (16, 27, 41, 49, 53, 57) and which transmits, to the stress-concentrating section (16, 27, 41, 49, 53, 57), a stress generated due to an external force applied to the stress-transmitting section, wherein the plate-shaped member (22, 33) extends in a predetermined in-plane direction; and a stress light-emitting section formed at the stress-concentrating section (16, 27, 41, 49, 53, 57) and formed of a stress light-emitting material which emits the light in response to a change of the stress; wherein the stress-concentrating section (16, 27, 41, 49, 53, 57) includes a plurality of individual stress-concentrating sections (16, 27, 41, 49, 53, 57) which are arranged with spacing distances with each other, the stress light-emitting section includes a plurality of individual stress light-emitting sections which are formed corresponding to the individual stress-concentrating sections (16, 27, 41, 49, 53, 57) respectively; and one of the individual stress light-emitting sections, which is provided for one of the individual stress-concentrating sections (16, 27, 41, 49, 53, 57) corresponding to the one individual stress light-emitting section, emits the light in response to the external force applied to the stress-transmitting section; characterized in that (a) an operation-indicating section, which indicates that a predetermined portion is a pushing section or a pulling section, is affixed to the predetermined portion, (b) at least one of the individual stress-concentrating sections (16, 27, 41, 49, 53, 57) is arranged on one surface of the plate-shaped member (22, 33), and at least one of the individual stress-concentrating sections (16, 27, 41, 49, 53, 57) and the operation-indicating section are arranged at positions different from each other in the in-plane direction, and (c) the stress light-emitting section emits the light such that the light which is emitted from the stress light-emitting section is visually recognizable directly without transmitting the light through the plate-shaped member (22, 33). a plate-shaped member (22, 33) which has a stress-concentrating section (16, 27, 41, 49, 53, 57) which causes a stress concentration, and a stress-transmitting section which is connected to the stress-concentrating section (16, 27, 41, 49, 53, 57) and which transmits, to the stress-concentrating section (16, 27, 41, 49, 53, 57), a stress generated due to an external force applied to the stress-transmitting section, wherein the plate-shaped member (22, 33) extends in a predetermined in-plane direction; and a stress light-emitting section formed at the stress-concentrating section (16, 27, 41, 49, 53, 57) and formed of a stress light-emitting material which emits the light in response to a change of the stress; wherein the stress-concentrating section (16, 27, 41, 49, 53, 57) includes a plurality of individual stress-concentrating sections (16, 27, 41, 49, 53, 57) which are arranged with spacing distances with each other, the stress light-emitting section includes a plurality of individual stress light-emitting sections which are formed corresponding to the individual stress-concentrating sections (16, 27, 41, 49, 53, 57) respectively; and one of the individual stress light-emitting sections, which is provided for one of the individual stress-concentrating sections (16, 27, 41, 49, 53, 57) corresponding to the one individual stress light-emitting section, emits the light in response to the external force applied to the stress-transmitting section; characterized in that (a) an operation-indicating section, which indicates that a predetermined portion is a pushing section or a pulling section, is affixed to the predetermined portion, (b) at least one of the individual stress-concentrating sections (16, 27, 41, 49, 53, 57) is arranged on one surface of the plate-shaped member (22, 33), and at least one of the individual stress-concentrating sections (16, 27, 41, 49, 53, 57) and the operation-indicating section are arranged at positions different from each other in the in-plane direction, and (c) the stress light-emitting section emits the light such that the light which is emitted from the stress light-emitting section is visually recognizable directly without transmitting the light through the plate-shaped member (22, 33). (a) an operation-indicating section, which indicates that a predetermined portion is a pushing section or a pulling section, is affixed to the predetermined portion, (b) at least one of the individual stress-concentrating sections (16, 27, 41, 49, 53, 57) is arranged on one surface of the plate-shaped member (22, 33), and at least one of the individual stress-concentrating sections (16, 27, 41, 49, 53, 57) and the operation-indicating section are arranged at positions different from each other in the in-plane direction, and (c) the stress light-emitting section emits the light such that the light which is emitted from the stress light-emitting section is visually recognizable directly without transmitting the light through the plate-shaped member (22, 33).