What is the vergence demand using a Variable Tranaglyph when the separation is measured as 4 cm at a distance of 80 cm when training divergence?

To find the vergence demand while training divergence with a Variable Tranaglyph, we first need to understand the relationship between the measured separation, the distance, and how these contribute to calculating the prism diopter demand.

In this scenario, the separation of the images is given as 4 cm, and the viewing distance is 80 cm. Vergence demand can be calculated using the formula:

[

\text{Prism Diopters} = \frac{\text{Separation (cm)}}{\text{Distance (m)}}

]

First, convert the distance from centimeters to meters. Since 80 cm is equivalent to 0.8 m, we can now use the formula:

[

\text{Prism Diopters} = \frac{4 , \text{cm}}{0.8 , \text{m}}

]

This results in:

[

\text{Prism Diopters} = \frac{4}{0.8} = 5 , \text{prism diopters}

]

Here, the vergence demand calculated is 5 prism diopters.

Since the context of the question indicates that this is while training divergence, we interpret this demand as base-in,