Patent ID: 11971163
Assignee: USHIO DENKI KABUSHIKI KAISHA
Field: Electrical machinery, apparatus, energy (Electrical engineering)
Classification: CPC F | IPC F

Claim 15:
16. A light source device comprising:
a plurality of LED elements that are dispersed and arranged in a plane direction orthogonal to an optical axis;
a first optical system that converts light emitted from each of the plurality of LED elements into collimated light;
a second optical system that focuses the collimated light emitted from the first optical system at a latter stage of the first optical system;
a substrate on which the plurality of LED elements are mounted;
a first lens holder that accommodates the first collimating optical system and is connected to the substrate in a fixed manner;
a second lens holder that accommodates the second collimating optical system and is capable of adjusting a relative position with respect to the first lens holder;
a through-hole penetrating the first lens holder at a predetermined location of the first lens holder in a direction parallel to the optical axis;
a groove having an inner diameter shorter than an inner diameter of the through-hole and being carved from a face of the first lens holder in a side of the first lens holder for a predetermined length in the direction parallel to the optical axis; and
a fixing member including a shaft section having an outer diameter shorter than the inner diameter of the through-hole and being insertable into the groove, and a head having an outer diameter longer than the inner diameter of the through-hole and being connected to the shaft section,
wherein the first optical system includes a first collimating optical system including optical components disposed corresponding to the plurality of LED elements and a second collimating optical system including optical components disposed corresponding to the plurality of LED elements at a latter stage of the first collimating optical system,
the second collimating optical system is capable of adjusting a relative optical positional relation with respect to the plurality of LED elements and the first collimating optical system when viewed in a direction of the optical axis in a state in which the plurality of LED elements and the first collimating optical system are fixed,
wherein the light source device satisfies the following formula:

0.1×D×(θ2/θ1)≤(ϕh−ϕp)/2≤D×(θ2/θ1)

where D is a maximum diameter of a light-emitting surface of the LED element, θ1 is a maximum light-acceptance angle of each optical component provided in the first collimating optical system, θ2 is a maximum light-acceptance angle of each optical component provided in the second collimating optical system, and ϕh is the inner diameter of the through-hole, and ϕp is the outer diameter of the shaft section of the fixing member.