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Introduction
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The *Area* lamp simulates light originating from a surface (or surface-like) emitter.
For example, a TV screen, office neon lamps, a window,
or a cloudy sky are just a few types of area lamp. The area lamp produces shadows with
soft borders by sampling a lamp along a grid the size of which is defined by the user.
This is in direct contrast to point-like artificial lights which produce sharp borders.

.. figure:: /images/render_blender-render_lighting_lamps_area_introduction_common-options.png

   Common options.


Lamp Options
============

Distance, Energy and Color
   These settings are common to most types of lamps,
   and are described in :doc:`Light Properties </render/blender_render/lighting/lights/lamp_panel>`.

   Note that the *Distance* setting is much more sensitive and important for *Area* lamps than for others;
   usually any objects within the range of *Distance* will be blown out and overexposed.
   For best results, set the *Distance* to just below the distance to the object that you want to illuminate.
Gamma
   Amount to gamma correct the brightness of illumination. Higher values give more contrast and shorter falloff.

   The *Area* lamp does not have light falloff settings. It uses an "inverse quadratic" attenuation law.
   The only way to control its falloff is to use the *Distance* and/or *Gamma* settings.
This Layer Only, Negative, Specular and Diffuse
   These settings control what the lamp affects,
   as described in :ref:`What Light Affects <bi-lamp-influence>`.


Shadows
=======

Area light ray-traced shadows are described here:
:doc:`Ray-traced Shadows </render/blender_render/lighting/lamps/area/raytraced_shadows>`.

When an *Area* light source is selected,
the *Shadow* panel has the following default layout:

.. list-table:: The *Shadow* panel when *Area* light source is selected.

   * - .. figure:: /images/render_blender-render_lighting_lamps_area_introduction_adaptive-qmc.png

          Adaptive QMC settings.

     - .. figure:: /images/render_blender-render_lighting_lamps_area_introduction_constant-jittered.png

          Constant Jittered settings.


Area Shape
==========

The shape of the area light can be set to *Square* or *Rectangle*.

.. list-table::

   * - .. figure:: /images/render_blender-render_lighting_lamps_area_introduction_square.png

          Square options.

     - .. figure:: /images/render_blender-render_lighting_lamps_area_introduction_rect.png

          Rectangle options.

Square / Rectangular
   Emit light from either a square or a rectangular area.
Size / Size X / Size Y
   Dimensions for the *Square* or *Rectangle*.

.. note:: Shape Tips

   Choosing the appropriate shape for your *Area* light will enhance the believability of your scene.
   For example, you may have an indoor scene and would like to simulate light entering through a window.
   You could place a *Rectangular* area lamp in a window (vertical) or from neons (horizontal)
   with proper ratio for *Size X* and *Size Y*. For the simulation of the light emitted by
   a TV screen, a vertical *Square* area lamp would be better in most cases.