Optical measurement system

1. An optical measurement system configured to perform optical measurement of a subject and to have an optical waveguide sensor chip mounted thereon, the optical waveguide sensor chip having a space for accommodating the subject, the space being defined by a plurality of surfaces including a first surface on which a functional layer is formed and along which an optical waveguide part is provided, the optical measurement system comprising:

a holding device configured to hold a bottom surface of the optical waveguide sensor chip, the holding device including a first window and a second window arranged along the optical waveguide part of the optical waveguide sensor chip so as to be spaced apart from the first window;

a light transceiver configured to emit an incident light to be incident on the optical waveguide sensor chip through the first window, and receive output light that has passed through the first surface via the optical waveguide part from the second window;

processing circuitry configured to process the output light to acquire information on the subject; and

a plurality of contact sensors configured to detect whether all contact states are ON in two or more detection positions located along an array direction of the first window and the second window to provide detection results, wherein

the processing circuitry is further configured to determine that the bottom surface of the optical waveguide sensor chip is in contact with the holding device based on the detection results from the contact sensors,

the contact sensors are detection switches configured to be pressed down by the bottom surface of the optical waveguide sensor chip,

for each contact sensor of the plurality of contact sensors, a position of the contact sensor satisfies L<A(1−(H/C)), A being a distance between a fixed holder and a movable holder, L being a distance between the fixed holder and the contact sensor, C being a height of the fixed holder, and H being a height of the contact sensor when the contact sensor is pressed down to be in the ON state, and

for one of the plurality of contact sensors, the position of the contact sensor further satisfies M<(1−B(H/D)), M being a distance in the left-right direction between a center axis of the contact sensor and a left contact part, B being a distance in the left-right direction between a right contact part and the left contact part, and D being a height of the left contact part,

wherein the holding device includes:

the fixed holder;

the movable holder configured to hold the optical waveguide sensor chip against the fixed holder from two of four side surfaces of the optical waveguide sensor chip; and

a mechanism configured to bias the movable holder toward the fixed holder.

2. The optical measurement system of claim 1 , wherein the plurality of contact sensors are located closer to the fixed holder than the first window and the second window are.

3. The optical measurement system of claim 1 , wherein

the mechanism includes a movement limiter configured to limit vertically upward movement of the optical waveguide sensor chip, the movement limiter being an engagement claw.

4. The optical measurement system of claim 3 , further comprising a side surface holder including a pair of contact surfaces configured to be in contact with two other side surfaces of the four side surfaces of the optical waveguide sensor chip, the other two of four side surfaces extending perpendicular to the two of four side surfaces, the contact surfaces being located in positions perpendicular to the fixed holder and the movable holder and facing each other, wherein

each of the contact sensors is located near one of the contact surfaces.

5. The optical measurement system of claim 1 , wherein the plurality of contact sensors are located near the fixed holder.

6. The optical measurement system of claim 4 , wherein the movement limiter is configured to be capable of engaging with an engagement part on a side surface of the optical waveguide sensor chip, and includes guide rails each extending on one of the side surface holders toward the movable holder from a position that is closer to the movable holder than the contact sensor is.

7. The optical measurement system of claim 1 , further comprising

the optical waveguide sensor chip that resides within the holding device, wherein

the optical waveguide sensor chip includes

a first grating on the first window side, configured to deflect the light to be incident on the optical waveguide part, and

a second grating on the second window side, configured to deflect the light to be emitted from the optical waveguide part, and

an array direction of the fixed holder and the movable holder is perpendicular to an array direction of the first grating and the second grating.

8. The optical measurement system of claim 1 , further comprising the optical waveguide sensor chip that resides within the holding device, wherein

the optical waveguide sensor chip includes

a first grating on the first window side, configured to deflect the light to be incident on the optical waveguide part, and

a second grating on the second window side, configured to deflect the light to be emitted from the optical waveguide part, and

an array direction of the fixed holder and the movable holder is parallel to an array direction of the first grating and the second grating.

9. The optical measurement system of claim 1 , wherein the holding surface has a color different from the plurality of contact sensors.

10. The optical measurement system of claim 1 , wherein

the light transceiver is configured to emit a plurality of light fluxes through the first window and receive a plurality of light fluxes that has passed through the first surface via the optical waveguide part from the second window, and

the processor is configured to process each of the light fluxes received by the light transceiver to acquire a plurality of pieces of information.