Ordered that the judgment is affirmed.
The defendant's contention that the County Court improperly limited his cross-examination is unpreserved for appellate review ( see People v Lyons, 81 NY2d 753; People v Maddrey, 282 AD2d 761). In any event, the County Court properly limited the defendant's cross-examination ( see People v Cato, 5 AD3d 394; People v Heung K. Sul, 234 AD2d 563).
Moreover, contrary to the defendant's contention, the County Court properly denied his application to have a handwriting expert examine the victim's diary. Any testimony by a handwriting expert would have been offered solely to impeach the victim's credibility, and the credibility of a witness may not be impeached through extrinsic evidence on matters collateral to the issues in the case ( see People v Alexander, 16 AD3d 515; People v Rendon, 301 AD2d 665; People v Ragland, 240 AD2d 598).
The sentence imposed was not excessive ( see People v Suitte, 90 AD2d 80).