How to specify an array of objects as a parameter or return value in JSDoc?

You should be more specific what you mean by JSDoc - this is a generic term covering pretty much all the JavaDoc-style documentation tools for JavaScript.

The syntax you used for array of strings looks like the one supported by Google Closure Compiler.

Using this, an array of Objects would be:

/**
 * @param {Array.<Object>} myObjects
 */

Or just an array of anything - this should work with pretty much all doc tools:

/**
 * @param {Array} myArray
 */

jsdoc-toolkit, JSDoc 3, and JSDuck support the following syntax to denote an array of objects:

/**
 * @param {Object[]} myArray
 */

EDIT

In case you know the keys and the variable type of the values you can also do:

/**
 * @param {Array.<{myNumber: Number, myString: String, myArray: Array}>} myObjects
 */

or

/**
 * @param {{myNumber: Number, myString: String, myArray: Array}[]} myObjects
 */