Image capturing apparatus and biometric information acquiring apparatus

A light detecting apparatus comprising:

• a light emitting section configured to emit light;
• a light detecting section configured to detect light from an observation target irradiated with the light emitted by the light emitting section;
• a mount section attached to a test subject that includes the observation target;
• a holding section configured to hold the light emitting section and the light detecting section and is detachably attached to the mount section;
• an illumination optical system configured to guide the light emitted by the light emitting section to the observation target;
• and
• an observation optical system configured to guide light from the observation target to the light detecting section, wherein
• the holding section is configured to hold the light emitting section and the light detecting section to secure a relative positional relationship between the light emitting section and the light detecting section,
• a relative positional relationship between the holding section and the mount section is determined by attaching the holding section to the mount section,
• the illumination optical system includes a diffusion member configured to diffuse the light emitted by the light emitting section, and
• an angle formed by an optical axis of the illumination optical system and an optical axis of the observation optical system is greater than 0° and less than 90°, wherein
• the mount section has an outer shape resulting from a second hollow pillar member connecting integrally with an outer circumference of a first hollow pillar member,
• a cross-sectional area of the second hollow pillar member, when cleaved on a plane perpendicular to an extension direction thereof, is less than a cross-sectional area of the first hollow pillar member, when cleaved on a plane perpendicular to an extension direction thereof,
• an angle formed by a central axis of the first hollow pillar member and a central axis of the second hollow pillar member is greater than 0° and less than or equal to 90°, and
• an empty hole of the first hollow pillar member and an empty hole of the second hollow pillar member are in communication inside the mount section.

A light detecting apparatus according comprising:

• a light emitting section configured to emit light;
• a light detecting section configured to detect light from an observation target irradiated with the light emitted by the light emitting section;
• a mount section attached to a test subject that includes the observation target;
• a holding section configured to hold the light emitting section and the light detecting section and is detachably attached to the mount section;
• an illumination optical system configured to guide the light emitted by the light emitting section to the observation target;
• and
• an observation optical system configured to guide light from the observation target to the light detecting section, wherein
• the holding section is configured to hold the light emitting section and the light detecting section to secure a relative positional relationship between the light emitting section and the light detecting section,
• a relative positional relationship between the holding section and the mount section is determined by attaching the holding section to the mount section,
• the illumination optical system includes a diffusion member configured to diffuse the light emitted by the light emitting section, and
• an angle formed by an optical axis of the illumination optical system and an optical axis of the observation optical system is greater than 0° and less than 90°, wherein
• a shape of the light detecting section or the observation target is asymmetrical,
• an optical axis of the illumination optical system is inclined toward a transverse direction of the light detecting section or the observation target, from an optical axis of the observation optical system,
• a diffusion angle of the diffusion member is wider in a wide angle direction than in a direction orthogonal to the wide angle direction, and
• the diffusion member is arranged on an optical path of the light emitted by the light emitting section, such that the wide angle direction of the diffusion member is substantially parallel to a longitudinal direction of the light detecting section or the observation target.