Yes "seriously"....just to help you "understand". Yes, a typical chrony does have electronic PHOTO sensors/components. Of course, what does Chrony know anyways!! lol
Ck out Chrony Owners Manual Section E:
. RIFLES: Be aware that the bullet line of travel will be as much as two inches BELOW the line of sight on scope-sighted rifles. Adjust upward in order NOT to hit the Chrony. If a bullet hits the Chrony, the Chrony will be destroyed, and will endanger you and others because of bullet ricochet and flying parts of the Chrony. Mark the Wire Rods with tape four inches above the Chrony unit for open-sighted rifles, and six inches for scope-mounted rifles.
Fig.4. Protective Shields
C. HANDGUNS: When shooting sub-sonic ammo, the muzzle blast will get to the Chrony before the bullet, which may cause erratic numbers. Increase distance from Chrony.
D. SHOTGUNS: because flying wads may go in any direction, protect the face of the Chrony by taping a thick piece of clear acrylic over the front of the unit. The acrylic must not extend above the face. Shooting Chrony Inc. offers such protection (see Accessories List). NOTE: When shooting without Diffusers one may substitute soda straws or wooden dowels for the Wire Rods. Hitting the Wire Rods with a bullet could break the Sensor Housings, whereas straws and dowels provide a safer sighting guide
E. MUZZLE LOADERS AND OTHER BLACK POWDER FIREARMS: In addition to protecting the face of the Chrony from wads and patches, you may cover the slots (eyes) of the photo sensors with strong and clear tape or Protective Shields (Fig.4) to prevent powder residue from entering these slots. Glass or clear plastic taped over these slots may also be used.
F. ARCHERY: Bow to Chrony distance should be at least an Arrow’s length. Blunt-tipped or flat-tipped arrows give more Accurate velocity measurements.
Fig 4 Shield
http://www.shootingchrony.com/images/shield.gif