Which type of external iPhone lens allows for a wider cinematic aspect ratio to be captured, often characterized by oval-shaped bokeh and horizontal lens flares?

The external iPhone lens that allows for a wider cinematic aspect ratio to be captured, often characterized by oval-shaped bokeh and horizontal lens flares, is an anamorphic lens. An anamorphic lens works by optically compressing a wider horizontal field of view into the standard rectangular sensor area of the iPhone. This means it records a broader scene than a typical spherical lens, but the captured image appears vertically stretched or "squeezed" when first viewed. To achieve the desired wider cinematic aspect ratio, which is the proportional relationship between the width and height of an image (for example, 2.39:1), this image must then be "desqueezed" in post-production or by a compatible camera application. Desqueezing stretches the image horizontally back to its correct proportions, creating the characteristic wide, letterbox look associated with cinema. The unique cylindrical optical elements within an anamorphic lens also cause light to behave distinctly. Bokeh, which is the aesthetic quality of the blur in the out-of-focus areas of an image, appears as elongated ovals rather than typical circles because the lens's horizontal compression stretches the out-of-focus light points. Similarly, bright light sources entering the anamorphic lens are refracted in a way that creates distinct horizontal streaks of light across the frame, known as horizontal lens flares, which are a signature visual element of anamorphic cinematography.