To provide a ring-like lighting device in which adjustment range of a working distance can be made wide.

The lighting device has a long hole 61 inclined by an angle θ on the side face of an adjusting ring 44, and an adjusting lock spring 48 is installed on this, thereby, the adjusting ring 44 can be fixed at an arbitrary position of the long hole 61 against a cylindrical body 42, and the adjusting ring 44 is fixed to the cylindrical body 42 moving in vertical direction, and at the same time the position of a step 55 moves. When the position of the step 55 moves downward, a substrate 41 is depressed downward and inclined by a substrate pressing spring 45 with an inclining axis 49 as a fulcrum and the LED 1 is changed in angle. By this angle change, working distance is changed and adjustment range of the working distance can be made wide.

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