Particle detector

A particle detector, comprising:

• an inspection light source configured to irradiate a flow cell with inspection light;
• the flow cell configured to
• allow a fluid containing a particle to flow therethrough, the flow cell including a semispherical reflective film configured to reflect reaction light generated by the particle irradiated with the inspection light, and a semispherical lens portion through which the reaction light reflected by the semispherical reflective film passes;
• an elliptical mirror that has a first focus at a position of the flow cell, and that is configured to reflect the reaction light having passed through the semispherical lens portion of the flow cell;
• and
• an optical detector disposed at a second focus of the elliptical mirror, the optical detector being configured to detect the reaction light reflected by the elliptical mirror.