Which test is used by introducing minus lenses until sustained blur occurs to assess amplitude?

Which test is used by introducing minus lenses until sustained blur occurs to assess amplitude?

• A. Push-up
• B. Minus lens
• C. MEM
• D. Nott's retinoscopy

Answer: (B)

Amplitude of accommodation is how much the eye can increase its focusing power to see near objects. In the minus-lens method, you keep the near target at a fixed distance (often about 40 cm) and gradually add minus lenses in front of the eye. Each added minus lens makes the eye work harder to maintain a clear image. When sustained blur is noticed, the power of the minus lens at that moment represents the eye’s amplitude of accommodation for that distance. This approach directly gauges how much accommodative power the eye can supply, without changing the target distance. Other tests work differently: the push-up method moves the target closer to measure near point but can be influenced by proximal cues; MEM assesses accommodative response using retinoscopy, not the accommodation’s maximum amplitude; Nott's retinoscopy is a refractive technique used to infer refractive status and accommodation in different ways, not specifically to quantify amplitude.

Amplitude of accommodation is how much the eye can increase its focusing power to see near objects. In the minus-lens method, you keep the near target at a fixed distance (often about 40 cm) and gradually add minus lenses in front of the eye. Each added minus lens makes the eye work harder to maintain a clear image. When sustained blur is noticed, the power of the minus lens at that moment represents the eye’s amplitude of accommodation for that distance. This approach directly gauges how much accommodative power the eye can supply, without changing the target distance.

Other tests work differently: the push-up method moves the target closer to measure near point but can be influenced by proximal cues; MEM assesses accommodative response using retinoscopy, not the accommodation’s maximum amplitude; Nott's retinoscopy is a refractive technique used to infer refractive status and accommodation in different ways, not specifically to quantify amplitude.